Title:

Processing method, manufacturing method of semiconductor device, and processing apparatus

Document Type and Number:

United States Patent Application 20080035851

Kind Code:

Abstract:

A processing method for selectively reducing or removing the region to be exposed with energy ray in a film formed on a substrate, comprising relatively scanning a first exposure light whose shape on the substrate is smaller than the whole first region to be exposed against the whole first region to be exposed to selectively remove or reduce the first region to be exposed, and exposing a whole second region to be exposed inside the whole first region to be exposed with a second exposure light to selectively expose the whole second region to be exposed.

Inventors:

Takeishi, Tomoyuki (Yokohama-shi, JP)
Kawano, Kenji (Yokohama-shi, JP)
Ikegami, Hiroshi (Hiratsuka-shi, JP)
Ito, Shinichi (Yokohama-shi, JP)
Takahashi, Riichiro (Yokohama-shi, JP)

Plaque It!

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2002-139083, filed May 14, 2002; and No. 2002-275894, filed Sep. 20, 2002, the entire contents of both of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a processing method for selectively processing a film to be exposed formed on a substrate, manufacturing method of a semiconductor device, and processing apparatus.

2. Description of the Related Art

In general, with advance of semiconductor element miniaturization, it has become essential to enhance precision of an alignment technique with a lower layer in a lithography process. To align a pattern already formed on a substrate with a pattern to be exposed at exposing latent image, an exclusive scope for detecting an alignment mark position has heretofore been used. However, since an offset surely exists between the exclusive scope for alignment and exposure axis in this method, a deviation is generated between the alignment scope and exposure axis because of an influence of thermal drift, and an alignment deviation of the alignment mark position is generated. Therefore, with the advance of the miniaturization of a semiconductor, a problem has occurred that magnitude of the alignment deviation of the alignment position largely influences yield of a chip.

To improve this, an exposure-through-the-reticle (ETTR) method of detecting alignment mark and exposing pattern along the same axis is considered as a promising alignment technique of the next generation. In the ETTR method, high-precision alignment can be realized. On the other hand, since light source with same wavelength of a DUV region as that of the exposure is used, light absorption is large in an anti-reflection film formed below a resist layer. A problem occurs that position information cannot be detected from the alignment mark in the anti-reflection film lower layer. Similarly, when the films formed on the alignment mark such as an organic insulating film and interlayer insulating film of SiN or SiC is opaque to an exposure light, position information of the alignment mark cannot be detected. Moreover, even when the alignment by ETTR is not performed, and even when contrast of an alignment light is weak, position information of alignment cannot be detected.

To solve the problem, there has been proposed a method of selectively remove the opaque film formed on the alignment mark with laser ablation before an alignment step. However, this method has a problem that particles generated at a laser ablation sticks to a device pattern region, which forms a critical defect.

BRIEF SUMMARY OF THE INVENTION

(1) According to one aspect of the present invention, there is provided a processing method for selectively removing or reducing a region to be processed of a film formed on a substrate, comprising: relatively scanning a first exposing light whose exposure region on the substrate is smaller than the whole first region to be exposed against the substrate to selectively process the whole first region to be processed of the film; and exposing a second region to be exposed inside the first region to be exposed with a second exposing light to selectively process the whole second region to be exposed.

(2) According to one aspect of the present invention, there is provided a manufacturing method of a semiconductor device, comprising:

preparing a substrate material in which an alignment mark is formed in or on a semiconductor substrate;

forming an anti-reflection film and resist film on the substrate material;

relatively scanning a first exposing light against the whole first region to be exposed on the substrate to selectively remove or reduce the anti-reflection film of a first region to be exposed including a region above which the alignment mark is formed;

exposing a second region to be exposed inside the whole first region to be exposed with a second exposing light to selectively remove or reduce the whole second region to be exposed of the anti-reflection film;

processing the anti-reflection film and subsequently transferring the substrate material to an exposure apparatus;

using the alignment mark in the exposure apparatus to perform alignment adjustment;

forming a latent image of a semiconductor circuit on the resist film after the alignment adjustment;

developing the resist film in which the latent image is formed to form a resist pattern; and

using the resist pattern to process the substrate material.

(3) According to one aspect of the present invention, there is provided a processing method for exposing each processing unit with an energy ray to selectively remove or reduce a whole region to be exposed of a film formed on a substrate, comprising:

exposing the processing unit of the substrate with the energy ray;

observing a gas member generated by exposure of the energy ray in an optical path of the energy ray;

measuring a size of the gas member; and

exposing the film to be exposed with the next energy ray, when the size of the gas member is smaller than a defined value.

(4) According to one aspect of the present invention, there is provided a processing method for exposing a whole region to be exposed of a substrate with an energy ray to selectively remove or reduce the whole region to be exposed, comprising:

passing a solution through the whole region to be exposed at a flow velocity V (μm/sec);

exposing whole the region to be exposed through which the solution flows with the energy ray having an oscillation frequency Z (1/sec) and a width W (μm) of a direction in which the solution flows; and

controlling the flow velocity V, width W, and oscillation frequency Z so as to satisfy the following relation: $V \geq 6\times\sqrt{\frac{W}{2} \times Z .}$

(5) According to one aspect of the present invention, there is provided a processing method for selectively removing or reducing a whole region to be exposed of an organic film formed on a substrate, comprising:

exposing the whole region to be exposed with an energy ray whose the exposure region on the substrate is smaller than the whole region to be exposed on conditions of an oscillation frequency f (1/sec) and energy density per pulse, on which the organic film can be removed; and

relatively scanning an exposure region of the energy ray against the whole region to be exposed on the substrate at a speed v (μm/sec),

wherein the oscillation frequency f and speed v satisfy the following relation: $6.0 \times {<
mn>10}^{- 5} \leq \frac{v}{f^{2}}$

(6) According to one aspect of the present invention, there is provided a processing apparatus for selectively removing or reducing a whole region to be exposed of a film formed on a substrate, comprising:

a substrate hold portion which holds the substrate;

a ray source which generates an energy ray to selectively reduce or remove a part of the film to be exposed;

a shaping portion which is disposed on an optical axis of the energy ray and which shapes the energy ray generated by the ray source;

a scan portion which relatively scans the energy ray shaped by the shaping against the whole region to be exposed on the substrate; and

a solution supply portion which changes a flow direction of a solution in accordance with a scan direction of the energy ray by the scan portion to continuously supply the solution to the surface of the whole region to be exposed on the substrate.

(7) According to one aspect of the present invention, there is provided a processing apparatus for selectively reducing or removing a whole region to be exposed of a film formed on a substrate, comprising:

a substrate hold portion which holds the substrate;

a ray source which generates an energy ray to selectively reduce or remove a part of the film to be processed;

a shaping portion which is disposed on an optical axis of the energy ray and which shapes the energy ray generated by the ray source and which emits energy rays having a irradiation shape on the substrate arranged by designed period; and

a scan portion which relatively scans the energy rays against the whole region to be exposed on the substrate in the designed period or less.

(8) According to one aspect of the present invention, there is provided a processing apparatus comprising:

a hold portion which holds a substrate;

an irradiation portion which generates an energy ray to reduce or remove a part of a film to be exposed of the substrate;

an observation/measurement portion which observes a gas member generated by abrasion of the film to be exposed by exposure of the energy ray on an optical path of the energy ray; and

a control portion which controls an exposure timing of the energy ray emitted from the exposure portion in accordance with an observation/measurement result of the observation/measurement portion.

(9) According to one aspect of the present invention, there is provided a processing apparatus for selectively reducing or removing a whole region to be exposed of a film formed on a substrate, comprising:

a hold portion which holds the substrate;

an exposure portion which exposures each processing unit set in the region to be exposed with an energy ray having an oscillation frequency Z (1/sec) and width W (μm) of one direction of an exposure region in the film to be exposed;

a supply portion which supplies a solution onto the region to be exposed of the film in one direction at a flow velocity V; and

a control portion which controls any one of the oscillation frequency Z, width W, and flow velocity V so as to satisfy the following relation: $V \geq 6\times\sqrt{\frac{W}{2} \times Z .}$

(10) According to one aspect of the present invention, there is provided a processing apparatus for selectively processing a whole region to be exposed of an organic film formed on a substrate, comprising:

a hold portion which holds the substrate;

an exposure portion which exposures the substrate with an energy ray whose exposure region on the substrate is smaller than the whole region to be exposed at an oscillation frequency f (1/sec) and energy density per pulse so that the organic film can be removed;

a scan portion which relatively scans an exposure region of the energy ray against the whole region to be exposed on the substrate at a speed v (μm/sec); and

a control portion to control at least one of the irradiation portion and scan portion so that the oscillation frequency f and speed v satisfy the following relation: $6.0 \times {<
mn>10}^{- 5} \leq \frac{v}{f^{2}}$

(11) According to one aspect of the present invention, there is provided a processing method comprising:

forming a first film on a substrate;

forming a second film on the first film;

selectively exposing the substrate with a first energy ray; and

maintaining at least a part of an irradiation of the first energy ray of the second film while reducing or removing the first film,

wherein the reducing or removing of the first film comprises: vaporizing the first film; or changing a transmittance.

(12) According to one aspect of the present invention, there is provided a manufacturing method of a semiconductor device, comprising:

preparing a substrate material in which an alignment mark is formed in or on a semiconductor substrate;

forming an anti-reflection film on the substrate material;

forming a resist film on the anti-reflection film;

selectively exposing the resist film of a region to be exposed including a region above which the alignment mark is formed with an energy ray;

maintaining at least a part of the resist film of the region to be exposed while reducing or removing the anti-reflection film;

transferring the substrate material to an exposure apparatus after processing the anti-reflection film;

using the alignment mark to perform alignment adjustment;

forming a latent image of a semiconductor circuit on the resist film after the alignment adjustment; and

developing the resist film to form a resist pattern,

wherein the processing of the anti-reflection film comprises: vaporizing the anti-reflection film; or changing a transmittance.

(13) According to one aspect of the present invention, there is provided a manufacturing method of a semiconductor device, comprising:

preparing a substrate material in which an alignment mark is formed in or on a semiconductor substrate;

forming an anti-reflection film and intermediate film on the substrate material;

selectively exposing the intermediate film of a whole region to be exposed including a region above which the alignment mark is formed with an energy ray;

maintaining at least a part of the intermediate film of the whole region to be exposed while reducing or removing the anti-reflection film;

forming a resist film on the intermediate film after reducing or removing the anti-reflection film;

transferring the substrate material in which the resist film is formed to an exposure apparatus;

using the alignment mark in the exposure apparatus to perform alignment adjustment;

forming a latent image of a semiconductor circuit on the resist film after the alignment adjustment; and

developing the resist film in which the latent image is formed to form a resist pattern; and

using the resist pattern to process the substrate material,

wherein the processing of the anti-reflection film comprises: vaporizing the anti-reflection film; or changing a transmittance.

(14) According to one aspect of the present invention, there is provided a processing method for exposing each processing unit with an energy ray to selectively reduce or remove a whole region to be exposed of a film formed on a substrate, comprising:

obtaining an intensity distribution of a reflected light from the substrate;

determining an energy amount of the energy ray with which each processing unit is irradiated from the intensity distribution of the reflected light; and

successively exposing the respective processing units with the energy ray based on the determined energy amount.

(15) According to one aspect of the present invention, there is provided a processing method for exposing each processing unit with an energy ray to selectively remove or reduce a whole region to be exposed of a film formed on a substrate, comprising:

obtaining an intensity distribution of a reflected light from the substrate;

classifying the intensity distribution of the reflected light for each region having an equal reflected light intensity;

setting the processing unit in accordance with the classified region;

determining an energy amount of the energy ray with which each processing unit is exposed in accordance with the reflected light intensity; and

successively exposing each processing unit with the energy ray based on the determined energy amount.

(16) According to one aspect of the present invention, there is provided a processing apparatus for selectively removing or reducing a whole region to be exposed of a film formed on a substrate, comprising:

a hold portion which holds the substrate;

an exposure portion which exposure each processing unit set in the region to be exposed with an energy ray;

a detection portion which exposes each processing unit with an observation light to detect a reflected light intensity from the processing unit;

a setting portion to set an energy amount of the energy ray with which each processing unit is exposed in accordance with the detected reflected light intensity; and

a control portion to control the energy amount of the energy ray with which each processing unit is exposed from the exposure portion in accordance with the energy amount set by the setting portion.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIGS. 1A to 1G are sectional views showing manufacturing steps of a semiconductor device according to a first embodiment;

FIG. 2 is a diagram showing a constitution of an optical processing apparatus according to the first embodiment;

FIG. 3 is a diagram showing a schematic constitution of an optical shaping portion;

FIG. 4 is a diagram showing a constitution of a view field setting system according to the first embodiment;

FIGS. 5A and 5B are diagrams showing an operation example of the view field setting system;

FIG. 6 is a diagram showing the constitution of the view field setting system according to the first embodiment;

FIG. 7 is a diagram showing a constitution of a slit/dot setting system according to the first embodiment;

FIG. 8 is a diagram showing the constitution of the slit/dot setting system according to the first embodiment;

FIGS. 9A to 9D are plan views showing an example of a diaphragm of the slit/dot setting system according to the first embodiment;

FIG. 10 is a plan view showing the example of the diaphragm of the slit/dot setting system according to the first embodiment;

FIG. 11 is a plan view showing a manufacturing step of the semiconductor device according to the first embodiment;

FIG. 12 is a diagram showing a surface state of a substrate from which a film has been removed in a method according to the first embodiment;

FIG. 13 is a diagram showing the surface state of the substrate from which the film has been removed in a related-art method;

FIGS. 14A and 14B are sectional views showing the manufacturing steps of the semiconductor device according to the first embodiment;

FIGS. 15A and 15B are diagrams showing the manufacturing steps of the semiconductor device according to a second embodiment;

FIGS. 16A and 16B are diagrams showing the manufacturing steps of the semiconductor device according to the second embodiment;

FIGS. 17A and 17B are diagrams showing the manufacturing steps of the semiconductor device according to a third embodiment;

FIGS. 18A and 18B are diagrams showing the manufacturing steps of the semiconductor device according to the third embodiment;

FIGS. 19A and 19B are diagrams showing the manufacturing steps of the semiconductor device according to a fourth embodiment;

FIGS. 20A and 20B are diagrams showing the manufacturing steps of the semiconductor device according to the fourth embodiment;

FIG. 21 is a diagram showing the manufacturing step of the semiconductor device according to a fifth embodiment;

FIG. 22 is a diagram showing the manufacturing step of the semiconductor device according to the fifth embodiment;

FIGS. 23A and 23B are sectional views showing the manufacturing steps of the semiconductor device according to a sixth embodiment;

FIGS. 24A to 24C are sectional views showing the manufacturing steps of the semiconductor device according to a seventh embodiment;

FIGS. 25A to 25C are plan views showing diaphragms mounted in an S/D diaphragm system according to an eighth embodiment;

FIGS. 26A and 26B are sectional views showing the manufacturing steps of the semiconductor device according to the eighth embodiment;

FIGS. 27A and 27B are sectional views showing the manufacturing steps of the semiconductor device according to a ninth embodiment;

FIG. 28 is a sectional view showing the manufacturing step of the semiconductor device according to the ninth embodiment;

FIGS. 29A and 29B are sectional views showing the manufacturing steps of the semiconductor device according to a tenth embodiment;

FIGS. 30A and 30B are sectional views showing the manufacturing steps of the semiconductor device according to an eleventh embodiment;

FIG. 31 is a sectional view showing the manufacturing step of the semiconductor device according to a twelfth embodiment;

FIGS. 32A to 32C are sectional views showing the manufacturing steps of the semiconductor device according to the twelfth embodiment;

FIGS. 33A to 33C are sectional views showing the manufacturing steps of the semiconductor device according to a 13th embodiment;

FIGS. 34A to 34F are sectional views showing the manufacturing steps of the semiconductor device according to a 14th embodiment;

FIGS. 35A to 35D are sectional views showing the manufacturing steps of the semiconductor device according to a 15th embodiment;

FIGS. 36A to 36C are sectional views showing the manufacturing steps of the semiconductor device according to a 16th embodiment;

FIG. 37 is a diagram showing a schematic constitution of a processing unit according to an 18th embodiment;

FIGS. 38A and 38B are plan views showing a processing state using the processing unit shown in FIG. 37;

FIGS. 39A and 39B are diagrams showing a constitution of a liquid supply unit;

FIGS. 40A to 40C are sectional views showing a problem of an alignment defect in forming a metal wiring of Al;

FIGS. 41A to 41F are sectional views showing the manufacturing steps of the semiconductor device according to a 19th embodiment;

FIGS. 42A to 42E are plan views showing an optical processing method according to a 20th embodiment;

FIGS. 43A and 43B are sectional views showing the manufacturing steps of the semiconductor device according to a 21st embodiment;

FIG. 44 is a plan view showing an irradiation region of one pulse of a laser beam;

FIGS. 45A and 45B are sectional views showing the manufacturing steps of the semiconductor device according to a 22nd embodiment;

FIG. 46 is a plan view showing an irradiation area of one pulse of the laser beam;

FIG. 47 is a diagram showing a constitution of a laser processing apparatus according to a 23rd embodiment;

FIG. 48 is a diagram showing the constitution of the laser processing apparatus according to the 23rd embodiment;

FIG. 49 is a diagram showing an example of an image obtained from a CCD camera of a laser processing apparatus;

FIGS. 50A to 50C are sectional views showing an example of a film structure according to the 23rd embodiment;

FIG. 51 is a diagram showing setting of an energy amount in each irradiation region in the processing method according to the 23rd embodiment;

FIG. 52 is a diagram showing the setting of the energy amount in each irradiation region in the processing method according to the 23rd embodiment;

FIG. 53 is a sectional view showing the constitution of the semiconductor device formed in the processing method according to the 23rd embodiment;

FIG. 54 is a diagram showing the setting of the energy amount in each irradiation region in a related-art processing method;

FIG. 55 is a sectional view showing the constitution of the semiconductor device formed in the related-art processing method;

FIG. 56 is a diagram showing an example of the image obtained from the CCD camera of the laser processing apparatus according to a 25th embodiment;

FIGS. 57A to 57C are sectional views showing an example of the film structure according to the 25th embodiment;

FIG. 58 is a diagram showing the setting of the energy amount in each irradiation region in the processing method according to the 25th embodiment;

FIG. 59 is a diagram showing the constitution of the laser processing apparatus according to a 26th embodiment;

FIG. 60 is a diagram showing the constitution of the laser processing apparatus according to the 26th embodiment;

FIGS. 61A to 61C are diagrams showing the optical processing method in which bubbles are not considered;

FIGS. 62A and 62B are diagrams showing the optical processing method according to a 27th embodiment;

FIG. 63 is a diagram showing a relation between a distance from a processed region and the number of pinholes in a case in which the processing is performed in consideration of the bubbles;

FIGS. 64A and 64B are diagrams showing an irradiation region shape of the laser beam in the optical processing according to the 27th embodiment;

FIGS. 65A and 65B are diagrams showing the irradiation region shape of the laser beam in collective processing;

FIGS. 66A and 66B are diagrams showing the irradiation region shape of the laser beam in the optical processing according to the 27th embodiment;

FIG. 67 is a diagram showing a relation between a diameter of the bubble and the number of pinholes;

FIG. 68 is a diagram showing a relation between a width W of the irradiation region and a bubble diameter φ generated at a processing time;

FIGS. 69A and 69B are sectional views showing the optical processing performed while an air current is generated in the processed region in the atmosphere;

FIGS. 70A and 70B are diagrams showing the manufacturing steps of the semiconductor device according to a 28th embodiment;

FIGS. 71A and 71B are diagrams showing the manufacturing steps of the semiconductor device according to a 29th embodiment;

FIGS. 72A and 72B are diagrams showing the manufacturing steps of the semiconductor device according to a 30th embodiment;

FIGS. 73A and 73B are diagrams showing the manufacturing steps of the semiconductor device according to a 31st embodiment;

FIGS. 74A to 74D are diagrams showing the manufacturing steps of the semiconductor device according to a 32nd embodiment;

FIGS. 75A and 75B are diagrams showing the manufacturing steps of the semiconductor device according to a 33rd embodiment;

FIGS. 76A to 76F are sectional views showing the manufacturing steps of the semiconductor device according to a 34th embodiment;

FIGS. 77A to 77H are sectional view showing the manufacturing steps of the semiconductor device according to a 35th embodiment;

FIG. 78 is a sectional view showing the semiconductor device of a chip-on-chip type according to a 36th embodiment;

FIGS. 79A to 79H are sectional views showing the manufacturing steps of the semiconductor device according to the 36th embodiment;

FIGS. 80A and 80B are plan views showing a relation between the processed region and solution flow according to a 37th embodiment;

FIG. 81 is a diagram showing a total defect area in the processed region after formation of the processed region with respect to v/f²;

FIG. 82 is a plan view showing the shape of the irradiation region on the substrate according to a 38th embodiment;

FIG. 83 is a characteristic diagram showing a total particle area with respect to total extension of a side according to the 38th embodiment; and

FIGS. 84A to 84D are diagrams showing a modification example of the irradiation region according to the 38th Embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described hereinafter with reference to the drawings.

First Embodiment

FIGS. 1A to 1G are sectional views showing manufacturing steps of a semiconductor device according to a first embodiment of the present invent on. As shown in FIG. 1A, a substrate 100 is prepared. For the substrate 100, an alignment mark 102 is buried/formed in a semiconductor substrate 101 of Si. An interlayer insulating film 104 is formed so as to coat wiring patterns 103 formed on the semiconductor substrate 101. The wiring patterns 103 are formed in a device region, and the alignment mark 102 is formed in the periphery of the device region.

Subsequently, as shown in FIG. 1B, an anti-reflection film 105 having a film thickness of 100 nm, and a chemical amplification positive resist film 106 having a film thickness of 300 nm are successively formed on the interlayer insulating film 104.

The anti-reflection film 105 is formed of an organic material in a rotary application method. The chemical amplification positive resist film 106 is a resist for an ArF light (wavelength 193 nm).

It is necessary to selectively remove the anti-reflection film 105 and resist film 106 on the alignment mark 102 which has a low transmittance with respect to an exposure light before performing alignment by an ETTR alignment method.

A region including the alignment mark 102 to be observed by the ETTR alignment method has a size, for example, of 100 μm×200 μm. Therefore, an opaque film of this region of 100 μm×200 μm is removed.

Next, a constitution of a laser processing apparatus for selectively removing the anti-reflection film 105 and resist film 106 on the alignment mark 102 will be described. FIG. 2 is a diagram showing the constitution of an optical processing apparatus according to the first embodiment of the present invention.

As shown in FIG. 2, an optical processing apparatus 200 includes a laser optical system 210, observation system 220, and laser processing section 230. First, the constitution of the laser optical system 210 will be described.

The laser optical system 210 includes: a laser oscillator 211; a laser oscillator control unit 212 which controls the laser oscillator 211; an optical system 214 which controls a laser beam 213 oscillated from the laser oscillator 211; an optical shaping unit 215 which controls a shape of the laser beam 213 passed through the optical system 214; and a condenser lens 216.

The laser beam 213 emitted from the laser oscillator 211 is successively transmitted through the optical system 214, optical shaping unit 215, and condenser lens 216, and a processing surface 100a of the substrate 100 disposed in the laser processing section 230 is exposed. The observation system 220 is inserted between the optical shaping unit 215 and condenser lens 216.

For example, a Q-Switch Nd-YAG laser oscillator is used as the laser oscillator 211. The laser beam oscillated from this Q-Switch Nd-YAG laser oscillator includes a basic wave (wavelength 1064 nm), second higher harmonic wave (wavelength 532 nm), third higher harmonic wave (wavelength 355 nm), and fourth higher harmonic wave (wavelength 266 nm). A wavelength which is absorbed by a film to be removed is selected from these wavelengths, and the substrate 100 is exposed with the laser beam having the selected wavelength.

Furthermore, a pulse width of the laser beam 213 emitted from the laser oscillator 211 is set to about 10 nsec. Moreover, it is possible to oscillate the laser beam of the laser oscillator 211 at 10 kHz at maximum. The oscillation of the laser beam 213 of the laser oscillator 211 is controlled by the laser oscillator control unit 212.

The laser beam 213 emitted from the laser oscillator 211 is incident upon the optical shaping unit 215 via the optical system 214.

As shown in FIG. 3, the optical shaping unit 215 is constituted of two systems: a view field setting system 250 in which an aperture for setting a view field; and a slit/dot setting system 260 in which an aperture for further miniaturizing the view field is formed. The substrate 100 is irradiated with the laser beam transmitted through a portion in which the aperture formed in the view field setting system 250 overlaps with that formed in the slit/dot setting system 260.

The view field setting system 250 forms the shape of the laser beam in a direction crossing at right angles to a scan direction described later. Moreover, the slit/dot setting system 260 forms the shape of the laser beam of the scan direction.

The constitution of the view field setting system 250 will be described with reference to FIG. 4. FIG. 4 is a diagram showing the constitution of a view field diaphragm setting system according to the first embodiment. As shown in FIG. 4, a plurality of, for example, four view field diaphragms 252a to 252d are mounted on a view field diaphragm mount plate 251. When the view field diaphragm mount plate 251 is rotated with a view field diaphragm selection mechanism 254, the diaphragm is selected from the view field diaphragms 252a to 252d.

A view field diaphragm rotation mechanism 255 for rotating the view field diaphragms 252a to 252d is disposed on the view field diaphragm mount plate 251. As shown in FIGS. 5A and 5B, the diaphragm rotation mechanism 255 rotates the view field diaphragm 252 by an angle θ2 corresponding to an inclination θ1 of the alignment mark of the substrate 100, which is measured by the observation system 220.

Moreover, as another mode of the view field setting system, a view field diaphragm system of a diaphragm blade type shown in FIG. 6 may also be used. This view field diaphragm system is shielded by four diaphragm blades 256a to 256d, and the laser beam is transmitted and shaped through a region surrounded by the diaphragm blades 256a to 256d. With the diaphragm type, it is possible to vary the shaping system shape of the laser beam.

The constitution of the slit/dot setting system 260 will be described with reference to FIGS. 7 and 8. FIGS. 7 and 8 are diagrams showing the constitution of the slit/dot setting system according to the first embodiment of the present invention.

As shown in FIG. 7, a second rotary plate 262 is disposed on a first rotary plate 261. A slit/dot diaphragm mount plate 263 (FIG. 8) on which the diaphragms are mounted is disposed on the second rotary plate 262. First and second rotation mechanisms 264, 265 are disposed to rotate the first and second rotary plates 261 and 262, respectively.

As shown in FIG. 8, for example, four diaphragms 266a to 266d are mounted on the slit/dot diaphragm mount plate 263. A translatory movement mechanism 267 translates/moves the slit/dot diaphragm mount plate 263 to select any one from the slit/dot diaphragms 266a to 266d.

Examples of four slit/dot diaphragms 266a to 266d are shown in FIGS. 9A to 9D. The diaphragm 266a shown in FIG. 9A transmits the laser beam shaped by the view field setting system 250 substantially as such. The diaphragm 266b shown in FIG. 9B shapes the beam in a slit shape. The diaphragms 266c, 266d shown in FIGS. 9C and 9D form the laser beams in dot shapes.

When the amount of a gas generated by laser exposure is high, the laser beam is scattered by the generated gas, and the processing is influenced in this manner, the slit shape may be used. Furthermore, when this tendency is remarkable, divided slit shapes may be used. When the above-described influence is little, a checkered lattice may be used. It is to be noted that a processing situation of a processed film is observed beforehand, and only one of these diaphragms can be mounted.

It is to be noted that the slit shape described herein indicates a shape in which a longitudinal direction of the irradiation shape is substantially equal to one side of the processed region, and a width, in the direction crossing at right angles to the longitudinal direction, is shorter than the other side of the processed region. Moreover, the irradiation shape of the dot shape indicates that both widths of the direction crossing at right angles to the irradiation shape are shorter than the width of the direction crossing at right angles to the processed region.

In this slit/dot diaphragm setting system, while the substrate stands still, the translatory movement mechanism 267 can translate/move the diaphragm mount plate 263 to scan the region to be exposed on the substrate. Since the plate is moved slightly by about several micrometers, a piezoelectric device may also be used to vibrate the plate in a translatory direction. It is to be noted that the slit may be fixed in the same method as that for use in a related-art exposure apparatus and the substrate and may also be relatively scanned against laser beam.

The first and second rotation mechanisms 264, 265 rotate the diaphragm mount plate 263 by an angle θ3 corresponding to the inclination θ1 of the alignment mark of the substrate 100, measured by the observation system 220, and adjust an irradiation position of the laser beam shaped by the view field setting system 250.

The aperture of the view field diaphragm for use herein has a shape substantially analogous to that of the processed region. The aperture is prepared in accordance with the processed region in a range of 10 μm to 500 μm (10 μm×10 μm to 500 μm×500 μm) of one side of the exposure region on the substrate. Moreover, the slit/dot diaphragm for use has a slit or dot width W of 2 to 10 μm. A plurality of slit/dot diaphragms are prepared in a range of a pitch P=2 W to 100 W. A throughput or particle generated amount is obtained beforehand, and the diaphragms are selectively used.

It is to be noted that as shown in FIG. 10, a mechanism similar to the view field setting system 250 may also be used to select a diaphragm plate in which the slits or dots are formed.

Another constitution of the slit/dot setting system 260 will be described with reference to FIG. 10. FIG. 10 is a diagram showing the constitution of the slit/dot setting system according to the first embodiment. As shown in FIG. 10, a plurality of, for example, four slit/dot diaphragms 266a to 266d shown in FIGS. 9A to 9D are mounted on the S/D diaphragm mount plate 267. An S/D diaphragm selection mechanism 269 rotates the S/D diaphragm mount plate 267 to select any one from the slit/dot diaphragms 266a to 266d.

An slit/dot diaphragm rotation mechanism 268 for rotating the S/D diaphragms 266a to 266d is disposed on the slit/dot diaphragm mount plate 267. The slit/dot diaphragm rotation mechanism 268 rotates the slit/dot diaphragm 252 by the angle θ3 corresponding to the inclination θ1 of the alignment mark of the substrate 100, measured by the observation system 220.

When the S/D setting system shown in FIG. 10 is used, a driving mechanism 242 moves the substrate 100 in parallel to change the irradiation position of the substrate. It is to be noted that a reflective plate such as a mirror is disposed between the substrate and view field setting system to change the angle of the reflective plate, and the irradiation position in the substrate can also be changed.

In this manner, an optical image shaped by the optical shaping unit 215 is transmitted through the observation system 220 and condenser lens 216 to irradiate the processing surface 100a of the substrate 100. The observation system 220 includes a half mirror 221 for taking the laser beam 213 from a light axis, and a camera for observation 222 for observing the laser beam taken out by the half mirror 221. For the observation system 220, a position to be processed on the substrate 100, exposing position, and processing situation are recognized as image information via the CCD camera 222.

This observation system 220 can be used to perform alignment adjustment of the laser beam irradiation position. Moreover, the process of the laser beam irradiation comprises: successively recognizing the image for the processed state; extracting the region to be processed from the image; and judging progress of the processing to adjust an exposure amount. For example, the exposure amount is reduced in the portion that the progress of processing is fast, and the exposure amount is increased in the portion that the progress of processing is fast. Moreover, it is recognized whether the processing ends. A difference of the image is obtained to recognize end of the processing. In a stage in which the difference of the image of the whole region to be exposed is substantially 0, the processing is ended. The processing can be controlled in this manner.

The observation system 220 also serves as a particle detection mechanism for observing the whole region to be exposed of the substrate 100 to count particles. The particles can be detected by calculating the number of pixels of a specific gradation range in a reflected light received by a CCD pixel. Furthermore, by an algorithm of:

1) regarding pixels disposed adjacent to each other longitudinally and laterally as one cluster to determine the number of defects; and

2) also regarding pixels disposed adjacent to each other longitudinally, laterally, and obliquely as one cluster to determine the number of defects, the defects can also be extracted. The particle detection mechanism compares the number of calculated defects with the minimum number of defects registered beforehand. When the number of detected defects is more than the minimum number of defects, a command is issued so as to successively perform treatment in a desired region. When the number is not more than the minimum number of defects, control can be executed to issue a command for shifting to the next processed region.

Moreover, the image is stored before/after laser exposure. When the difference is taken and is substantially 0, the processing in the portion is stopped. In another case, the control is executed to continue the processing.

Next, the laser processing section 230 will be described. A holder 231 is constituted in a tray-like shape in which a dam for storing a solution 239 is disposed in a peripheral portion. For example, pure water is used as the solution 239.

A stage 232 in which the substrate 100 can be laid/held is disposed in a middle portion in the holder 231. The substrate 100 is rotated by a rotation mechanism 233 connected to the stage 232. For the rotation of the substrate 100, a rotary angle is controlled by a sensor 235 and rotation control mechanism 234. It is to be noted that in the present embodiment the rotation mechanism 233 is connected to a driving mechanism 242. The holder 231 is moved in horizontal and vertical directions to change the exposure position of the laser beam. The condenser lens 216 can be miniaturized by the rotation mechanism 233 and driving mechanism 242. It is possible to miniaturize a laser processing system in this manner.

The holder 231 further includes a window 236 for covering the solution in which the processing surface of the substrate 100 is submerged. The window is transparent to the laser beam. The laser beam 213 oscillated from the laser oscillator 211 is transmitted through the window 236 and solution 239 so that the processing surface 100a of the substrate 100 is exposed.

Furthermore, a solution flow unit 237 is disposed to allow the solution 239 pooled in the holder 231 to flow. The solution flow unit 237, which is basically a pump, is connected to the holder 231 through pipes 238a, 238b, and the solution 239 is circulated. Moreover, a flow direction can be controlled with respect to the direction of relative movement of the substrate 100 and laser beam.

Additionally, the present apparatus includes a piezoelectric device 240 disposed in the back surface of the holder 231, and a piezoelectric device driving control circuit 241 which controls the driving of the piezoelectric device 240. The piezoelectric device 240 gives an ultrasonic vibration to the solution 239 of the irradiation region of the laser beam of at least the processing surface 100a of the substrate 100, and bubbles generated by the irradiation with the laser beam can be removed.

Moreover, a laser beam source is used as a light source for the processing in the present apparatus, but the present invention is not limited to this. Any light may be used, as long as a wavelength is absorbed by the film to be processed and desired processing can be performed, that is, the film thickness can be reduced, or the film can be removed. For example, when the wavelength is absorbed by a visible or ultraviolet region in an organic or inorganic film, the light of a tungsten or Xe flash lamp is condensed and used. In this case, film thickness reduction is confirmed.

The present apparatus relates to the processing in water, but can also be applied to a treatment in the atmosphere, pressurizing treatment, and reduced pressure treatment, and the holder structure can be used in accordance with the respective treatments.

Next, the removing of the resist film 106 and anti-reflection film 105 using the optical processing apparatus 200 will be described.

The substrate is transferred to the optical processing apparatus 200 shown in FIG. 2. A notch and wafer edge of the substrate are detected to adjust alignment of a laser beam axis and substrate. Moreover, the inclination of the view field diaphragm and Slit/dot diaphragm is adjusted in accordance with the inclination of the alignment mark 102.

Next, for the shape of the light to be emitted, a predetermined region to be removed is determined to have a longitudinal size 100 μm×lateral size 200 μm, and the optical shaping unit is used to shape the laser beam in a desired shape. Moreover, in the present embodiment, the Slit/dot diaphragm for shaping the laser beam in one slit shape with a longitudinal size 100 μm×lateral 5 μm is used.

Next, as shown in FIG. 1C, the solution flow unit 237 is operated to allow the solution 239 to flow between the window 236 and substrate 100. In this state, the laser beam is relatively scanned against the substrate to remove the region to be processed of the film.

A method of relatively scanning the substrate against light may comprise: fixing the light axis of the laser beam to use the driving mechanism 242; or using the optical shaping unit and translating/moving, for example, the Slit/dot mount plate 263 to scan the substrate.

The wavelength of the laser beam is absorbed by the anti-reflection film for use in a lithography process. An energy density per pulse is appropriately adjusted so that the whole region to be ablated can satisfactorily be removed without damaging a region other than the whole region to be ablated. The energy density per pulse is usually in a range of 0.1 J/cm²·pulse to 0.5 J/cm²·pulse.

Since the solution 239 exists on the exposure portion at a laser beam exposure, heat generated by the exposure with the laser beam can be removed in the processing surface 100a of the substrate 100. Furthermore, an energy of evaporant generated by the irradiation with the laser beam can be decreased.

The window 236 prevents the solution 239 pooled in the holder 231 from being scattered at a laser processing time. Moreover, the window prevents dust from sticking to the surface of the semiconductor substrate 101 from above.

The substrate 100 is exposed with the laser beam, and the Slit/dot diaphragm mount plate 263 is translated/moved. When the Slit/dot diaphragm mount plate 263 is translated/moved, as shown in FIG. 11, an exposure region 272 with the laser beam relatively scans against the whole region to be exposed 271 on the substrate, and the anti-reflection film 105 and resist film 106 of the whole region to be exposed are removed.

It is to be noted that the particles generated at exposure by the exposure are removed in the liquid flow. It has been confirmed by experiments that the particles stick onto a downstream side. Then, for a scan direction of the exposure region, the generated particles can be removed in the same direction as that of the liquid flow during the processing. Therefore, the generation of the particles is reduced. The solution flow unit 237 allows the solution 239 pooled in the holder 231 to flow so that bubbles generated in the irradiation position of the laser beam by the irradiation with the laser beam can continuously be removed. Furthermore, the solution is circulated in a constant direction in a constant flow rate so as to prevent irregular disturbance from being generated in the laser beam. The solution flow unit 237 may be driven, when the laser processing is actually performed.

Next, after the solution 239 pooled in the holder 231 is discharged, the processing substrate 100 is rotated at a high speed, and a liquid in the surface is roughly removed. Thereafter, the processing substrate 100 is further transferred to a second solvent removing apparatus and heated. A heating temperature of the substrate 100 was set to 200° C. The substrate 100 is heated here in order to remove an adsorbed liquid in the surface of a resist film 306 and to obtain the same exposure environment in the whole resist film surface. When the treatment is not performed, acid generated in the exposure moves by a slight amount of liquid left in the film in a portion in contact with the liquid, and a pattern defect is caused.

Subsequently, the substrate 100 is transferred to an exposure apparatus. As shown in FIG. 1D, the alignment mark 102 of the substrate 100 is detected by an alignment detector using an alignment light (first energy line) 107 which has the same wavelength as an exposure wavelength. At this time, since the anti-reflection film 105 on the alignment mark 102 is removed, satisfactory detection sensitivity is obtained. It is to be noted that the alignment mark 102 cannot be detected, when the anti-reflection film 105 on the alignment mark 102 is not removed as in the related art.

As shown in FIG. 1E, an exposure portion 106a of the resist film 106 is irradiated with an exposure light (second energy line) to form a latent image of a circuit pattern in the resist film 106. After the latent image forming step, the substrate 100 is transferred to a heating apparatus for a PEB step to perform a heating treatment (PEB) of the processing substrate. The heating treatment is performed to cause catalyst reaction of acid of a used resist (chemical amplification type resist).

After this heating treatment, as shown in FIG. 1F, the substrate 100 is transferred to develop the image of the resist film 106 and to form resist patterns 109. Alignment precision of the formed resist patterns 109 is not more than ±5 nm.

Subsequently, as shown in FIG. 1G, the resist patterns 109 are used as masks to etch the anti-reflection film 105 and interlayer insulating film 104 by RIE.

FIG. 12 shows a substrate surface state from which the anti-reflection film 105 and resist film 106 are removed in the above-described method. Moreover, FIG. 13 shows the substrate surface state as a reference example in which the laser is collectively exposed the whole region to be ablated the films are removed.

As seen from FIG. 13, when the films are removed by the collective exposure, a large number of particles 284 exist and cannot completely be removed in the periphery and inside of the whole region to be ablated. Furthermore, peels 283 of the resist film formed on the anti-reflection film are generated around the whole region to be ablated.

When the films are removed in the method of the present embodiment, as compared with the related-art method shown in FIG. 13, peels 281 of the upper-layer resist are reduced. It is seen that the number of particles 282 sticking to the periphery and inside of the whole region to be ablated decreases.

A reason of the decrease of the number of particles will be described hereinafter. When a exposure region once is broad, the bubble generated by the exposure becomes larger than the whole region to be ablated. Therefore, a large number of particles adsorbed in bubble surfaces stick to the inside/outside of the whole region to be ablated.

On the other hand, when the exposure region is thinned into the slit shape, and the exposure region is relatively scanned against the whole region to be ablated on the substrate, the bubble generated once becomes small, and the bubble does not easily-contact the substrate. Therefore, the number of particles sticking to the inside/outside of the whole region to be ablated is reduced.

As a result of measurement of the generated bubble, in a case in which a whole region to be ablated of the film is collectively removed, a radius of the generated bubble was R=120 μm. On the other hand, in the exposure with the laser beam having the slit shape with a width of 5 μm, the bubble radius was R=25 μm. In the exposure with the laser beam having the slit shape, the size of the bubble is reduced as compared with the collective exposure. It has been seen from this result that the diameter of the bubble generated with one ablation is controlled to be reduced, and the sticking particles can be reduced.

However, even the above-described method is incomplete for removing the particles in the processed region. The sticking particles in the alignment mark cause problems of an increase of read inaccuracy in reading the alignment mark, or read error. Moreover, when the particles stick to the outside of the alignment mark, particularly to a device region, a pattern forming defect is caused, and yield disadvantageously drops.

A method in which the number of particles sticking to the inside/outside of the whole region to be ablated can further be reduced will be described hereinafter.

First, a processing method for preventing the particles from sticking to the inside of the whole region to be ablated will be described. An apparatus for use in removing the film is similar to that described in the first embodiment.

FIGS. 14A and 14B are sectional views showing the manufacturing steps of the semiconductor device according to the first embodiment of the present invention.

As shown in FIG. 14A, for the resist film and anti-reflection film on a predetermined the whole region to be ablated (longitudinal 100 μm×lateral 200 μm), a laser beam 110 is shaped in the slit shape (longitudinal 100 μm×lateral 3 μm) having a width smaller than that of the alignment mark, and is exposed with the resist film and anti-reflection film. While the laser beam (first processing light) 110 is scanned to the other end from one end of the processed region, the ablation is performed. At this time, a small amount of particles 111 stick to the substrate surface.

Here, assuming that an oscillation frequency is f, scan speed is v, and a slit having a width t is scanned, the number n of overlap exposures performed in one scan is represented by:
n=tf/v (1).
That is, when the oscillation frequency f=250 Hz, and scan speed v=30 μm/sec, the number n of overlap exposures=25 irradiations in the slit width t=3 μm.

When the number n of overlap exposure increases, damages by exposure are easily caused in various regions formed in the lower layer of the anti-reflection film, such as a substrate Si, mark, and interlayer insulating film. That is, the number of overlap exposures is appropriately selected by the thickness and material of the anti-reflection film or the film type or thickness of the anti-reflection film lower layer. Usually n is selected between 1 and 50.

In equation (1), when the number n of overlap exposures is less than one, the overlap of the exposure regions is removed. A film which cannot completely be removed exists in the whole region to be ablated. This residual film in the whole region to be ablated is peeled, when the adjacent exposure region is exposed. Critical particles are generated. That is, n needs to be set to at least 1 or more.

Subsequently, as shown in FIG. 13B, a laser beam (second processing light) 112 is scanned to the other end from one end. Furthermore, when the laser beam 112 is similarly repeatedly reciprocated/scanned, it is possible to remove the particles remaining above the alignment mark. Here, the scanning was performed in the solution 239 pooled in the holder 231 in order to alleviate an influence onto the resist film by the heat generated by the abrasion. Moreover, the solution 239 was circulated in the constant direction at the constant flow rate so that the bubbles generated in the region irradiated with the laser beam by the irradiation with the laser beam can continuously be removed and to such an extent that disturbance is not generated in the laser beam in the solution flow unit 237.

In this process, the observation system 220 constituted of the CCD camera is used to count the particles inside/outside the whole region to be ablated. Subsequently, the image is stored before/after the exposure, and the difference of the number of particles is obtained. When the difference is substantially 0, the processing in the portion is stopped; otherwise, the processing is controlled to be continuously performed.

It has been confirmed that the alignment precision of the substrate pattern with the exposure pattern is improved by the above-described step.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this embodiment. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may be ended even with a slight amount of the processed film remaining in the whole region to be ablated. For example, even when the film thickness of the processed film is halved, and contrast is bad, the alignment can be performed.

Second Embodiment

In the first embodiment, the method of forming the exposure region of the laser beam in the slit shape and reciprocating/scanning the laser beam against the whole region to be ablated to remove the particles sticking to the whole region to be ablated has been described.

However, at the processing by the exposure in this method, the exposure region on the substrate is constantly fixed in the slit shape having a constant area, and the light is reciprocated/scanned in the whole region to be ablated. Therefore, when the alignment precision is not sufficient with respect to the exposure position and the whole region to be ablated, and every time the reciprocating scan is repeated, the processed position deviates. This causes a problem that the particles are newly generated from a edge of the whole region to be ablated.

To solve the problem, in the present embodiment, a method will be described which comprises: reducing the exposure region of the laser beam on the substrate in consideration of the alignment precision in the vicinity of the edge of the whole region to be ablated and reducing the number of the particles generated in the vicinity of the edge of the whole region to be ablated to prevent the particles from sticking to the processed region.

FIGS. 15A, 15B, 16A and 16B are diagrams showing the manufacturing steps of the semiconductor device according to a second embodiment of the present invention. It is to be noted that in FIGS. 15A, 15B, 16A and 16B, the same parts as those of FIG. 1B are denoted with the same reference numerals, and the description thereof is omitted. FIGS. 15A and 16A are sectional views, and FIGS. 15B and 16B are plan views of the processed region.

In a first scan, as shown in FIG. 15, exposure region 120 is relatively scanned against the substrate 100 in a middle portion of a whole region to be ablated 121, and scanned to the other end from one end of the whole region to be ablated to remove the anti-reflection film 105 and resist film 106 of the whole region to be ablated 121. It is to be noted that reference numeral 122 denotes the exposure region of the laser beam 120.

As described above, when the alignment precision of the exposure region with the hole region to be ablated is not sufficient in the reciprocating scan in this state in the first embodiment, the edge of the whole first region to be ablated is exposed, and processed, and the particles stick into the region 121.

Then, In a second and subsequent state, as shown in FIGS. 16A and 16B, when an exposure region 124 approaches the edge of the whole region to be ablated 121, in consideration of the alignment precision, an exposure region 125 is set to be smaller than the an exposure region 122 in the middle portion of the processed region 121 by the view field setting system 250.

Thereby, new particles can be prevented from being generated from a region other than the whole region to be ablated 121 by the influence of the alignment error in the vicinity of the edge of the whole region to be ablated 121. Moreover, when an exposure region is reduced, the bubble 125 generated in the edge of the whole region to be ablated becomes smaller than a bubble 123 generated in the middle portion of the whole region to be ablated. Moreover, the amount of particles 111 decreases. Therefore, the particles 111 adsorbed in the surfaces of the bubbles 125 are also prevented from sticking to the substrate surface.

By this method, it is further possible to prevent the particles from sticking into the processed region as compared with the method described in the first embodiment.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may be ended with a slight amount of the processed film remaining in the processed region.

Third Embodiment

In the second embodiment, the method has been described which comprises: relatively scanning the exposure region against the whole region to be ablated substrate; and reducing the area of the exposure region in consideration of the alignment precision in the vicinity of the edge of the whole region to be ablated. Thereby, the new particles are inhibited from being generated from the region other than the whole region to be ablated, the diameter of the generated bubble is reduced, and the particles adsorbed in the bubble surface are prevented from sticking to the substrate surface.

In a third embodiment, for a purpose similar to that of the second embodiment, the exposure region is relatively scanned against the whole region to be ablated, and scanned to the other end from one end of the whole region to be ablated. When the position of exposure region comes close to the edge of the whole region to be ablated, a scan speed is reduced, and the alignment precision in the vicinity of the edge of the whole region to be ablated is further improved. Moreover, when the diameter of the bubble generated per unit time is reduced, the particles are prevented from sticking into the whole region to be ablated. This method will be described.

FIGS. 17A, 17B, 18A and 18B are diagrams showing the manufacturing steps of the semiconductor device according to the third embodiment of the present invention. It is to be noted that in FIGS. 17A, 17B, 18A and 18B, the same parts as those of FIG. 1B are denoted with the same reference numerals, and the description thereof is omitted. FIGS. 17A and 18A are sectional views, and FIGS. 17B and 18B are plan views of the processed region.

In second and subsequent scans, when the exposure region approaches the edge of the whole region to be ablated, a scan speed of a laser beam 133 is reduced (FIGS. 18A and 18B) as compared with a time when a exposure region 130 is scanned in the middle portion of a whole region to be ablated 131 (FIGS. 17A and 17B). The scan speed of the exposure region is adjusted by adjusting a translation rate of the diaphragm mount plate. Reference numerals 131, 134 denote the exposure region 130, 133 on the substrate.

Since the scan speed of the exposure region becomes slow in the edge of the whole region to be ablated 131, the exposed area per time decreases in the vicinity of the edge of the whole region to be ablated 131. Therefore, the diameter of a bubble 135 generated in the unit time also decreases, the particles 111 adsorbed in the surfaces of the bubbles 135 do not easily contact the substrate surface, and the particles are prevented from sticking to the inside/outside of the whole region to be ablated 131.

In this process, the observation system 220 constituted of the CCD camera is used to count the particles inside/outside the whole region to be ablated. Subsequently, the image is stored before/after the exposure, and the difference of, the number of particles is obtained. When the difference is substantially 0, the processing in the portion is stopped; otherwise, the processing is controlled to be continuously performed.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may be ended with the slight amount of the processed film remaining in the processed region.

Fourth Embodiment

In the first embodiment, the method of scanning the thinned laser beam constantly having the constant exposure region in the whole region to be ablated to remove the anti-reflection film or resist film has been described. However, when the exposure region is reciprocated/scanned, there is an error in the alignment precision between the laser beam and whole region to be ablated against the scan direction.

In this case, when the exposure region having the same shape is repeatedly reciprocated/scanned, an influence of the alignment error is exerted, and the region other than the whole region to be ablated is exposed. As a result, every time exposure region is reciprocated/scanned in the whole region to be ablated, new particles are generated, and it is difficult to completely remove the particles.

To solve the problem, in a fourth embodiment, the alignment precision of the exposure region against the processed region is considered, and a long side of the exposure region formed in the slit shape is gradually reduced.

This embodiment will be described in more detail with reference to FIGS. 19A, 19B, 20A and 20B. FIGS. 19A, 19B, 20A and 20B are diagrams showing the manufacturing steps of the semiconductor device according to the fourth embodiment of the present invention. It is to be noted that in FIGS. 19A, 19B, 20A and 20B, the same parts as those of FIG. 1B are denoted with the same reference numerals, and the description thereof is omitted. FIGS. 19A and 20A are sectional views, and FIGS. 19B and 20B are plan views of the processed region.

FIGS. 19A and 19B show a first scan state. Moreover, FIGS. 20A and 20B show a second and subsequent scan state. As shown in FIGS. 19A, 19B, 20A and 20B, a length of an exposure region 144 in the % longitudinal direction in the second scan of a laser beam 143 is set to be shorter than that of an exposure region 142 of a laser beam 140 in the first scan.

In this case, even when the reciprocating scan is repeated, the region, other than the whole region to be ablated is not exposed with the light. As a result, it is possible to reduce the particles generated outside the whole region to be ablated and to prevent the particles from sticking to the film.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may be ended with the slight amount of the processed film remaining in the processed region.

Fifth Embodiment

In the first embodiment, the thinned light is scanned in the whole region to be ablated to remove the anti-reflection film or resist film. However, in this method, when there is the alignment error of the scan direction between the exposure region and the whole region to be ablated, and when the exposure region is constantly reciprocated/scanned in the whole region to be ablated, the edge of the whole region to be ablated by the previous exposure is exposed for every repeated reciprocating scan. A large amount of new particles are generated from the portion other than the whole region to be ablated.

To solve the problem, in a fifth embodiment, the alignment precision of the position of exposure region is considered with respect to the scan direction, and a scan range of the exposure region in the whole region to be ablated is gradually reduced every increase of the number of scans.

This embodiment will be described in more detail with reference to FIGS. 21 and 22. FIGS. 21 and 22 are diagrams showing the manufacturing steps of the semiconductor device according to the fifth embodiment of the present invention. It is to be noted that in FIGS. 21 and 22, the same parts as those of FIG. 1B are denoted with the same reference numerals, and the description thereof is omitted.

FIG. 21 shows the first scan state. Moreover, FIG. 22 shows the second scan state. As shown in FIGS. 21 and 22, the scan range of an exposure region 151 in the second scan is set to be smaller than that of an exposure region 150 in the first scan.

For this reciprocating scan, even when the reciprocating scan is repeated, the region other than the whole region to be ablated is not exposed with the light. As a result, it is possible to reduce the particles generated outside the whole region to be ablated and to prevent the particles from sticking to the film.

As described above, in the first to fifth embodiments, the shape of exposure region is set to a long slit shape, and the exposure region is relatively against the whole region to be ablated to remove the anti-reflection film or resist film. However, the shape of exposure region is not limited to the long slit shape. The exposure region may be exposed with a light divided in dot shapes, and the inside of the predetermined processed region may also be scanned.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may also be ended with the slight amount of the processed film remaining in the processed region.

Sixth Embodiment

In the first to fifth embodiments, the method has been described comprising: reciprocating/scanning the light whose exposure region is smaller than the whole region to be ablated to remove the particles sticking into the processed region.

However, this method has a problem that time is consumed in the reciprocating scan and throughput drops. Furthermore, because of the exposure with the light having the long slit shape, problems occur that an influence of heat strain increases in the alignment mark formed in the anti-reflection film lower layer and that the lower layer is easily damaged.

In a sixth embodiment, a method of shortening a treatment time while inhibiting the lower layer from being damaged by the alignment mark will be described.

FIGS. 23A and 23B are sectional views showing the manufacturing steps of the semiconductor device according to the sixth embodiment. It is to be noted that in FIGS. 23A and 23B, the same parts as those of FIG. 1B are denoted with the same reference numerals and the description thereof is omitted.

As shown in FIG. 23, the method first comprises: scanning an exposure region 160 of the slit shape against the whole region to be ablated to remove the anti-reflection film 105 and resist film 106 of the processed region. In this state, the particles 111 exist in the whole region to be ablated.

Subsequently, in second and subsequent exposure, as shown in FIG. 23B, the exposure region 161 is shaped only by the view field setting system and has substantially the same size as that of the whole region to be ablated to remove the particles. At this time, in consideration of the alignment precision, an actual exposure region may also be smaller than the whole region to be ablated so as to prevent a portion other than a the whole region to be ablated from being generated particles.

Even in this method, in the same manner as in the second to fifth embodiments, it is possible to prevent the particles from sticking into the whole region to be ablated.

Moreover, here, first the exposure region is the long slit shape and is relatively scanned against whole region to be ablated to remove the anti-reflection film or resist film. However, the shape of the exposure region is not limited to a thin rectangular shape. The processed region may also be exposed with the light divided in dots, and the dotted light may also be scanned in the whole region to be ablated.

As described above, in at least the first processing, the exposure region having the long slit shape is scanned to ablate the region, so that the particles are inhibited from being generated. Thereafter, when the processed region is exposed with the light, it is possible to remove the particles in the whole region to be ablated.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

In the present embodiment the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may also be ended with the slight amount of the processed film remaining in the processed region.

Seventh Embodiment

Next, a method of removing the particles scattered to the inside/outside of the whole region to be ablated will be described.

FIGS. 24A to 24C are sectional views showing the manufacturing steps of the semiconductor device according to a seventh embodiment of the present invention. It is to be noted that in FIGS. 24A to 24C, the same parts as those of FIG. 1B are denoted with the same reference numerals and the description thereof is omitted.

In the present embodiment, the substrate submerged in a flowing liquid is exposed with the light.

As shown in FIG. 24A, an exposure region 170 shaped in the slit shape is scanned to a first edge B1 from a first start point M1 in the whole region to be ablated. At this time, the direction of the flow of the solution by the solution flow unit is a substantially antiparallel direction against the scan direction. That is, the an exposure region 170 moves toward an upstream side of the solution flow. Since the particles flow with the liquid flow, the particles 111 stick in the whole region to be ablated and on the downstream side of the liquid flow.

Next, as shown in FIG. 24B, the exposure region 170 is scanned to a second edge B2 from a second start point M2 between the first start point M1 and first edge B1. At this time, the flow of the solution 239 by the solution flow unit 237 at a first scanning is reversed.

When the exposure region is relatively scanned against the whole region to be ablated in this manner, the whole region to be ablated is processed. Even in this state, by the flow of the solution 239 by the solution flow unit 237, the particles do not exist outside the whole region to be ablated, and all remain in the whole region to be ablated.

Subsequently, as shown in FIG. 24C, an exposure region 171 is repeatedly reciprocated/scanned in the whole region to be ablated, and the particles remaining in the whole region to be ablated are removed.

Moreover, by the repeated reciprocating scan, the new particles can be prevented from being generated from the edge of the whole region to be ablated. Therefore, as described above in the embodiments, the view field setting system is varied in the vicinity of the edge of the whole region to be ablated. Thereby, the exposure region is reduced, the scan speed is reduced, and an optimum method is appropriately selected without any sticking particle.

Furthermore, instead of the exposure with the slit shaped light, as described in the sixth embodiment, the shape of exposure region is changed to the shape substantially having the size of the whole region to be ablated, and the collective exposure may also be performed.

In this process, the observation system 220 constituted of the CCD camera is used to count the particles inside/outside the whole region to be ablated. Subsequently, the image is stored before/after the laser irradiation, and the difference of the number of particles is obtained. When the difference is substantially 0, the processing in the portion is stopped; otherwise, the processing is controlled to be continuously performed.

When the above-described method is used, it is possible to ablate the region without any sticking particle inside/outside the whole region to be ablated.

When the exposure region is scanned from the vicinity of the processed region middle as in the present embodiment, the laser beam is preferably scanned in a direction opposite to that of the flow of the solution 239 by the solution flow unit 237 to further inhibit the particles from sticking.

In the present embodiment, the processed film on the alignment mark is completely removed, but the present invention is not limited to this. For example, when the alignment mark can be detected by the optical system for use in the alignment measurement, the processing may also be ended with the slight amount of the processed film remaining in the processed region.

Eighth Embodiment

In the method described in the second to seventh embodiments, the generated amount of particles can be reduced. However, an area which can be ablated once is small, a scan time for the whole region to be ablated is consumed, and this causes a problem that the throughput largely drops.

To solve the problem, in the present embodiment, on order to largely shorten the treatment time, a mask in which a plurality of slit-shaped or dot-shaped apertures of the slit/dot diaphragm system are disposed is used to shape the laser beam. Examples of the mask are shown in FIGS. 25A to 25C. FIGS. 25A to 25C are plan views showing the masks mounted in the Slit/dot diaphragm system according to an eighth embodiment of the present invention. In masks 180a, 180b shown in FIGS. 25A and 25B, a plurality of slit-shaped apertures 181a, 181b are formed. Moreover, a plurality of dot-shaped apertures 181c are formed in a mask 180c shown in FIG. 25C.

When a pitch of a plurality of apertures disposed in the mask is less than twice the length of the aperture of a pitch direction, the lights passed through the adjacent apertures diffract each other. As a result, since the substrate is exposed with an interference light, abnormality is caused in the processed shape.

Therefore, the pitch of the plurality of apertures disposed in the mask is preferably not less than twice the length W of the aperture of the pitch direction. The light having the shape analogous to that of the aperture formed in the mask is incident upon the substrate.

The pitch of the plurality of apertures disposed in the mask which are adjacent to each other in the scan direction is set to be ½ or less of the length of the whole region to be ablated of the scan direction. Thereby, the treatment time can be shortened.

It is to be noted that the lights interfere with each other even with the pitch of 2 W or more and the irradiation shape cannot be kept to be rectangular. In this case, the pitch may set to be large.

Furthermore, it is preferable to adjust the pitch of the apertures disposed adjacent to each other in the scan direction in the mask so that the pitch of the processing lights emitted adjacent to each other in the scan direction on the substrate is larger than a diameter of the bubble generated by the irradiation with the processing light. The pitch of the processing lights which is disposed adjacent to each other in the scan direction and with which the substrate is irradiated is not more than the diameter of the bubble generated by the irradiation with the processing light. Then, the bubbles generated adjacent to each other contact each other. As a result, irregular disturbance is further caused in the laser beam, and it becomes difficult to accurately process the region.

FIGS. 26A and 26B are sectional views showing the manufacturing steps of the semiconductor device according to the eighth embodiment of the present invention. In FIGS. 26A and 26B, the same parts as those of FIG. 1B are denoted with the same reference numerals and the description thereof is omitted.

As shown in FIGS. 26A and 26B, a plurality of slit-shaped laser beams 180, 181 are reciprocated/scanned in the whole region to be ablated to remove the anti-reflection film 105, resist film 106, and particles 111.

For the processing, the slit/dot diaphragm may be fixed and the substrate may be moved to process the whole region to be ablated by the relative scan. Here, the substrate is fixed and the slit/dot diaphragm is moved to remove the whole region to be ablated.

Since the distance to scan the each exposure region is reduced, a time required for processing the whole region to be ablated is reduced in inverse proportion to the number of disposed slits.

Moreover, by the repeated reciprocating exposure, the particles sticking to the whole region to be ablated are removed. Thereby, the particles can be prevented from sticking into the processed region, and additionally the treatment time can largely be shortened.

In this process, the observation system 220 constituted of the CCD camera is used to count the particles inside/outside the whole region to be ablated. Moreover, the image is stored before/after the, and the difference is obtained. When the difference is substantially 0, the processing in the portion is stopped; otherwise, the processing is controlled to be continuously performed.

Moreover, here, a plurality of slit-shaped exposure regions are relatively scanned against the whole region to be ablated to remove the anti-reflection film or resist film. However, the shape of the exposure region is not limited to the slit shape. As shown in FIG. 25C, a plurality of dot-shaped divided regions may be disposed and reciprocated/scanned within the processed region.

Additionally, with the arrangement of the dot shapes, light intensity weakens in the edge of the multi-slit exposure region, the multi-slit exposure region is scanned, and an unprocessed region is formed in a long-side direction in the whole region to be ablated. At this time, the dots are arranged so that the long sides of the dots overlap with each other at scanning. When the plurality of dots are arranged in this manner, the processing is possible without any unprocessed region or without any particle sticking onto the treated substrate.

In the present embodiment, as shown in FIGS. 26A and 26B, the exposure region is reciprocated/scanned to remove the whole region to be ablated, but the present invention is not limited to this. Even when the exposure region 180, 181 are scanned in any one direction for periods twice the number of reciprocations performed in FIGS. 26A and 26B, the processed surface is exposed with the same amount of beams. At this time, the length of the scan direction of the region in which a plurality of slits are formed in the slit/dot diaphragms is preferably not less than the predetermined number of scans of the whole region to be ablated multiplied by the length of the scan direction of the aperture of the view field diaphragm. The length of the region in which the slits are formed is set by multiplying the length of the aperture analogous to the whole region to be ablated by the number of scans. Then, the necessary number of scans of the laser beam can be performed without stopping the slit/dot diaphragm. When the processing is performed without stopping the slit/dot diaphragm, the reciprocating movement of the slit/dot diaphragm and the adjustment of the laser beam can be omitted, and the processing time can be shortened.

Therefore, the pitch of the plurality of apertures arranged in the mask is preferably twice or more times the length W of the aperture of the pitch direction. The light having the shape analogous to that of the aperture formed in the mask is incident upon the substrate.

At this time, in consideration of the alignment precision, the scan speed of the multi-slits in the vicinity of the boundary or the predetermined processed region, and irradiation energy or area in the irradiation region are controlled to prevent the particles from being generated. For the method, in consideration of the generated situation of the particles and arrangement of the slits, an optimum method may appropriately be selected.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

Ninth Embodiment

In a ninth embodiment, a method of shortening the treatment time and additionally removing the particles flied/scatted inside/outside the whole region to be ablated will be described.

FIGS. 27A, 27B and 28 are sectional views showing the manufacturing steps of the semiconductor device according to the ninth embodiment of the present invention. In the present embodiment, the substrate submerged in the flowing liquid is irradiated with the light.

As shown in FIG. 27A, a multi-slit exposure region R is reciprocated/scanned between the first start point in the whole region to be ablated and first end (edge 1). At this time the direction of the liquid flow is changed in accordance with the scan direction so that the scan direction is antiparallel the direction of the liquid flow. In this state, since the particles flow in the liquid flow, the particles stick in the whole region to be ablated and on the downstream side of the liquid flow.

The start point is set so that an interval between the start point and the end of whole region to be ablated on a first scan direction side is not less than the width of the multi-slit exposure region R. If the interval is not more than the width of the multi-slit exposure region R, the outside of the processed region is processed.

Subsequently, as shown in FIG. 27B, the multi-slit exposure region R is reciprocated/scanned to the other end (edge 2) disposed opposite to a edge 1 of the whole region to be ablated from the second start point. The direction of the liquid flow is changed in accordance with the direction of the scan so that the direction of the scan is antiparallel that of the liquid flow (the direction of the liquid flow is reverse to the direction to the first boundary from the first start point). Even in this state, since the particles flow in the liquid flow, the particles do not stick to the outside of the processed region, and all remain in the whole region to be ablated.

Subsequently, as shown in FIG. 28, a laser beam 190 having substantially the same size as that of the processed region is emitted. By the irradiation with the laser beam 190, the particles which cannot completely be removed by the reciprocating scan of the multi-slit irradiation region R and which remain in the processed region are removed.

In the processing process, the observation system 220 constituted of the CCD camera is used to count the particles inside/outside the processed region. Moreover, the image is stored before/after the exposure, and the difference is obtained. When the difference is substantially 0, the processing in the portion is stopped; otherwise, the processing is controlled to be continuously performed.

In the present embodiment, the exposure region in the second and subsequent exposure is changed/reduced by focus shift, but the present invention is not limited to this. For example, a zoom function is imparted to the image forming optical system 216 of FIG. 2, and magnification in the second and subsequent exposure may be slightly reduced for the exposures.

With the use of the above-described method, the multi-slits are used to remarkably shorten the treatment time, and the processed shape can be obtained without any sticking particle inside/outside the whole region to be ablated.

Even when the laser processing is performed in the atmosphere, high-pressure air or low-pressure air the effect of the present embodiment can be confirmed.

Tenth Embodiment

FIGS. 29A and 29B are sectional views showing the manufacturing steps of the semiconductor device according to a tenth embodiment of the present invention. It is to be noted that in FIGS. 29A and 29B, the same parts as those of FIG. 1B are denoted with the same reference numerals and the description thereof is omitted. Concretely, a pressure control unit is added to the air current unit shown in FIG. 2, and the processed region of the circulated solution is controlled.

As shown in FIGS. 29A and 29B, in a state in which a pressure of 10 atm is added to the substrate, exposure region 300, 301 shaped in the slit shapes are reciprocated/scanned against the substrate to remove the whole region to be ablated of the anti-reflection film 105 and resist film 106.

As a result, as compared with the processing in the similar method at atmospheric pressure, the bubble diameter generated at the exposing can be reduced, and the number of particles sticking to the inside/outside of the whole region to be ablated can be remarkably reduced.

Moreover, also in the present embodiment, in the same manner as in the above-described other embodiments, in consideration of the alignment precision of the whole region to be ablated against the position of exposure region, in order to prevent the edge of the whole region to be ablated from being exposed and to prevent new particles from being generated, the area of the exposure region can be reduced in the edge of the whole region to be ablated. Alternatively, the scan speed of the exposure region against the whole region to be ablated is reduced. For the method, an optimum method is appropriately selected in which only a small amount of particles stick.

Eleventh Embodiment

In an eleventh embodiment, a method will be described comprising: considering the alignment precision of the poison of exposure region against the whole region to be ablated; and reducing the area of the exposure region at the second and subsequent scans.

In the present embodiment, the method will be described comprising: changing a focal position in which the image is formed in the whole region to be ablated on the substrate to control the area of the exposure region and to prevent the particles generated from the edge of the whole region to be ablated from sticking into the whole region to be ablated.

First, as shown in FIG. 30A, in the same manner as in the above-described embodiments, a first processing light 311 whose exposure region on the substrate is thinned to be smaller than the whole region to be ablated is relatively scanned against the whole region to be ablated to remove the anti-reflection film 105 and resist film 106 of the processed region.

Additionally, at this time, instead of forming the image on the anti-reflection film 105 which is a processing object, a distance between the optical system and substrate 100 is intentionally set so that a light distribution can spread on the anti-reflection film 105.

Therefore, the region actually exposed with the light on the anti-reflection film becomes larger than the region restricted by the view field setting system. On the other hand, an energy density per pulse weakens as the light distribution spreads. Therefore, the energy density per pulse is appropriately controlled so as to prevent the region having a light intensity necessary for the processing in the spread light from having a size which is not more than a desired size.

Instead of forming the image on the anti-reflection film 105 which is the processing object, the distance between the optical system and substrate 100 intentionally set so that the light distribution spreads on the anti-reflection film. At this time, conditions of a distance D between the image forming position and treatment substrate are as follows:

(1) the distance D is different from at least a best focus; and

(2) it is assumed that a deviation amount between the exposure position of the laser beam and the substrate by the align