DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Embodiment of Substrate Processing Apparatus and Substrate Transfer Method

[0060] FIG. 1 is a plan view showing an apparatus arrangement of a substrate processing apparatus according to a preferred embodiment of the present invention. FIG., 2 is an elevation of the apparatus. FIG. 3 is a view for explaining one example of a wafer thermoregulator of the apparatus shown in FIGS. 1 and 2 .

[0061] The substrate processing apparatus according to the embodiment comprises a process chamber 1 serving as the first chamber and a wafer supply portion 10 arranged in the outer air. The process chamber 1 is arranged as a part of an exposure apparatus. The process chamber 1 has an internal space in which an exposure process portion 20 for transferring a pattern to a wafer is arranged and a pressure-reduced He atmosphere is maintained.

[0062] The wafer supply portion 10 has a wafer carrier support portion 101 , on which a wafer carrier 102 storing the wafer is placed manually or by an automatic transfer apparatus. A preliminary chamber 2 which contains a second transfer mechanism 8 is connected to the first chamber 1 .

[0063] In order to exchange the wafer between the different atmospheres, a load-lock chamber 3 serving as the second chamber is arranged between the chamber 1 and the wafer supply portion 10 . The load-lock chamber 3 includes a first gate valve 4 on the outer air side to shield the load-lock chamber 3 from the wafer supply portion 10 in the outer air (external environment), and a second gate valve 5 on the chamber side to shield the load-lock chamber 3 from the preliminary chamber 2 .

[0064] The load-lock chamber 3 also includes an exhaust mechanism 12 for exhausting gas from the load-lock chamber 3 , an He gas supply portion 13 for supplying He gas into the load-lock chamber 3 , and an N ₂ gas supply portion 14 for supplying N ₂ gas into the load-lock chamber 3 .

[0065] The load-lock chamber 3 has a wafer table 6 designed, e.g., to store one or a plurality of wafers.

[0066] The load-lock chamber 3 and the second transfer mechanism 8 are arranged to transfer the wafers one by one. The internal volume of the load-lock chamber 3 is set to a minimum size to minimize an exhaustion time. A device for heating the wafer must be arranged upstream of the load-lock chamber 3 to achieve such downsizing.

[0067] A first transfer mechanism 7 for transferring the wafer between the wafer carrier 102 on the wafer carrier support portion 101 and the load-lock chamber 3 is arranged in the outer air. The second transfer mechanism 8 for transferring the wafer between the load-lock chamber 3 and a process station (exposure process portion) 20 is arranged in the preliminary chamber 2 connected between the chamber 1 and the load-lock chamber 3 .

[0068] A wafer thermoregulator 11 is arranged midway along a path where the first transfer mechanism 7 transfers the wafer. One example of the wafer thermoregulator is shown in FIG. 3 . The wafer thermoregulator 11 shown in FIG. 3 is arranged as follows. A housing 115 accommodates a heater 111 for generating high-temperature heat, a fan 112 for supplying air through the heater 111 , and a filter 114 serving as a particle removing device at the front end of the fan 112 . A temperature measuring device 113 for measuring the heated air temperature is attached to the housing 115 .

[0069] The operation of the wafer transfer in the exposure apparatus according to the present invention will be described next. The arm of the first transfer mechanism 7 is inserted into the wafer carrier 102 in the outer air, and one wafer is chucked by this arm. By bending the arm which chucks the wafer, the wafer is extracted from the wafer carrier 102 . After that, a sensor (not shown) checks the state of the atmosphere in the load-lock chamber 3 .

[0070] In this case, assume that the load-lock chamber 3 is set in the atmospheric state. The transfer mechanism 7 rotates the arm toward the load-lock chamber 3 , stretches the arm after confirming that the gate valve 4 is open, and then loads the wafer into the load-lock chamber 3 to place the wafer on the wafer table 6 .

[0071] In the path where the transfer mechanism 7 transfers the wafer from the wafer carrier 102 into the load-lock chamber 3 , the wafer thermoregulator 11 heats the wafer by blowing the heated gas such as air to the wafer.

[0072] The heating temperature of the wafer is determined in consideration of the reduction of the wafer temperature caused by an adiabatic expansion along with a vacuum suction in the load-lock chamber 3 . That is, the heating temperature (target temperature) of the wafer is determined in consideration of the decrease in temperature so as to heat the wafer cooled by the adiabatic expansion to the predetermined temperature. The decrease in wafer temperature can be theoretically calculated by the volume, pressure before the vacuum suction, and ambient temperature in the load-lock chamber 3 , the vacuum pressure obtained by the vacuum suction operation, a time required for the vacuum suction, and the heat exchange ratio of the gas and wafer in the load-lock chamber 3 .

[0073] The decrease in wafer temperature caused by the adiabatic expansion is calculated in advance. A heating time is calculated on the basis of the temperature of heated air and the heat exchange ratio of the outer air and wafer. The heated air may be blew to the wafer for the calculated time.

[0074] The heating time of the wafer by the wafer thermoregulator 11 may be determined by heating time data input manually or by an external apparatus, or may be calculated by an arithmetic unit or control unit arranged inside or outside the exposure apparatus in accordance with the above calculation condition input manually or by the external apparatus. Alternatively, the heating time of the wafer may be calculated on the basis of various data stored in the calculation unit or control unit, which are obtained when the immediately preceding wafer is loaded into the load-lock chamber 3 .

[0075] The temperature of the heated air may be obtained by measuring the temperature of the heated air at the outlet of the wafer thermoregulator 11 , or by using a theoretical value. The temperature of the heated air blew from the wafer thermoregulator 11 is preferably controlled to a constant value. This makes it easy to calculate and control the heating time. In addition, variations in heating effect (the temperature after heating) of the plurality of wafers can be reduced.

[0076] The thermoregulator may be arranged in a way different from the examples shown in FIGS. 1 to 3 . The station may be arranged in front of the load-lock chamber, and an electric heater, electromagnetic heater, or the like may be arranged in the station. The temperature of the wafer placed in the station may be thermally regulated by the heater. Alternatively, a device for irradiating a wafer with light from an infrared lamp or the like to heat the wafer may be arranged as the thermoregulator.

[0077] In the exposure apparatus of this embodiment, a wafer temperature measuring device 9 for measuring the temperature of the heated wafer in a noncontact manner is preferably arranged. The wafer temperature measuring device 9 measures the wafer temperature during heating. Heating is controlled by the thermoregulator 11 on the basis of the calculation result, thereby more accurately controlling the wafer temperature.

[0078] At this stage, it is preferable that the noncontact temperature measuring device 9 be used to minimize the contamination and the like of the wafer, and to sense the temperature of the wafer surface. However, a contact temperature measuring device may be used. For example, a contact temperature measuring device can be arranged in the arm or the like of the first transfer mechanism 7 , which is brought into contact with the wafer. In this case, the temperature can be controlled with high precision as well.

[0079] After setting the heated wafer in the load-lock chamber 3 , the transfer mechanism 7 moves the arm backward to refract the arm from the load-lock chamber 3 . After that, the gate valve 4 is closed, and the vacuum exhaust valve 122 is opened to exhaust the air from the load-lock chamber 3 till the predetermined vacuum degree. When exhausting, the temperature of the atmosphere in the load-lock chamber 3 is reduced by adiabatic expansion, and the wafer coming into contact with this atmosphere is cooled.

[0080] When the atmosphere in the load-lock chamber 3 have been completely exhausted (when the vacuum exhaust valve 122 is closed), an He gas supply source 132 is opened to supply He gas into the load-lock chamber 3 in order to make the atmosphere in the load-lock chamber 3 equivalent to that in the chamber 1 and preliminary chamber 2 . When the atmosphere in the load-lock chamber 3 become the pressure-reduced He atmosphere with the pressure substantially equal to that in the chamber 1 and the preliminary chamber 2 , the gate valve 5 is opened, and the arm of the second transfer mechanism 8 is inserted into the load-lock chamber 3 .

[0081] The wafer has been transferred to the process station (in this case, the exposure process portion) 20 by the second transfer mechanism 8 . At this stage, the wafer temperature is reduced to reach the predetermined temperature. Hence, the predetermined wafer process (in this case, exposure) can be immediately performed in this state.

[0082] In the substrate processing apparatus described above, the substrate is processed in the pressure-reduced He atmosphere in the chamber 1 . However, in another application, the substrate may be processed in the pressure-reduced atmosphere (pressure-reduced environment) of gas other than He gas in the chamber 1 . Furthermore, in still another application, the substrate may be processed in an atmosphere with predetermined pressure such as atmospheric pressure in the chamber 1 . Furthermore, the substrate may be processed in so-called vacuum environment whose pressure is less than several Pa such as 10 ⁻¹² to several Pa. That is, the present invention can apply to all apparatuses in which the substrate in the atmospheric environment is exposed to the pressure-reduced atmosphere (for example, the pressure-reduced atmosphere is once formed in order to purge the atmosphere).

[0083] Embodiment of Exposure Apparatus

[0084] An exposure apparatus (exposure process portion) 20 according to an embodiment of the present invention will be described by exemplifying a scanning exposure apparatus. FIG. 6 is a front view showing an example of the main structure of the scanning exposure apparatus according to the preferred embodiment of the present invention. This exposure apparatus, or a part of which including a wafer stage is arranged in the above first process chamber, and performs exposure for the substrate (wafer).

[0085] In FIG. 6, a lens barrel surface plate 96 is supported by a floor/base 91 via a damper 98 . The lens barrel surface plate 96 supports a reticle stage surface plate 94 , and also supports a projection optical system 97 arranged between a reticle stage 95 and a wafer stage 93 .

[0086] The wafer stage 93 having a chuck 90 is supported on a stage surface plate 92 arranged on the floor/base 91 , and holds the wafer set on the chuck 90 to position the wafer. The reticle stage 95 is supported on the reticle stage surface plate 94 supported by the lens barrel surface plate 96 , and can move while mounting the reticle serving as a master on which a circuit pattern is formed. Exposure light for exposing the reticle mounted on the reticle stage 95 onto the wafer on the wafer stage 93 is emitted from an illumination optical system 99 .

[0087] The wafer stage 93 is scanned in synchronism with the reticle stage 95 . During scanning of the reticle stage 95 and the wafer stage 93 , the positions of both stages are continuously detected by interferometers, respectively, and the detection results are fed back to driving units of the reticle stage 95 and wafer stage 93 . Hence, the scanning start positions of both the stages can be accurately synchronized, and the scanning speed in a constant-speed scanning region can be controlled with high precision. While both the stages scan the projection optical system 97 , the reticle pattern is exposed on the wafer, and the circuit pattern is transferred.

[0088] Embodiment of Semiconductor Production System

[0089] A production system for a semiconductor device (semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin-film magnetic head, a micromachine, or the like) using an exposure apparatus according to the present invention will be exemplified. The system performs maintenance services such as trouble shooting, periodic maintenance, and software distribution for manufacturing apparatuses installed in a semiconductor manufacturing factory by utilizing a computer network or the like outside the manufacturing factory.

[0090] FIG. 7 shows the overall system cut out at a given angle. In FIG. 7 , reference numeral 1101 denotes an office of a vendor (apparatus supply manufacturer) which provides a semiconductor device manufacturing apparatus. Examples of the manufacturing apparatus are semiconductor manufacturing apparatuses for various processes used in a semiconductor manufacturing factory, such as pre-process apparatuses (lithography apparatus including an exposure apparatus, resist processing apparatus, and etching apparatus, an annealing apparatus, a film formation apparatus, a planarization apparatus, and the like) and post-process apparatuses (assembly apparatus, inspection apparatus, and the like). The office 1101 comprises a host management system 1108 which provides a maintenance database for the manufacturing apparatus, a plurality of operation terminal computers 1110 , and a LAN (Local Area Network) 1109 which connects the host management system 1108 and computers 1110 to build an intranet or the like. The host management system 1108 has a gateway for connecting the LAN 1109 to Internet 1105 serving as an external network of the office, and a security function for limiting external accesses.

[0091] Reference numerals 1102 to 1104 denote manufacturing factories of the semiconductor manufacturer as users of manufacturing apparatuses. The manufacturing factories 1102 to 1104 may belong to different manufacturers or the same manufacturer (pre-process factory, post-process factory, and the like). Each of the factories 1102 to 1104 is equipped with a plurality of manufacturing apparatuses 1106 , a LAN (Local Area Network) 1111 which connects these apparatuses 1106 to construct an intranet, and a host management system 1107 serving as a monitoring apparatus which monitors the operation status of each manufacturing apparatus 1106 . The host management system 1107 in each of the factories 1102 to 1104 has a gateway for connecting the LAN 1111 in the factory to the Internet 1105 serving as an external network of the factory. Each factory can access the host management system 1108 of the office 1101 of vendor from the LAN 1111 via the Internet 1105 . The security function of the host management system 1108 authorizes access of only a limited user. More specifically, the factory can notify the vendor via the Internet 1105 of status information (e.g., the symptom of a manufacturing apparatus in trouble) representing the operation status of each manufacturing apparatus 1106 . Also, the factory can receive, from the vendor, response information (e.g., information designating a remedy against the trouble, or remedy software or data) corresponding to the notification, or maintenance information such as the latest software or help information. Data communication between the factories 1102 to 1104 and the office 1101 of the vendor and data communication via the LAN 1111 in each factory adopt a communication protocol (TCP/IP) generally used in the Internet. Instead of using the Internet as an external network of the factory, a high-security dedicated network (e.g., ISDN) which inhibits access of a third party can be adopted. The host management system is not limited to the one provided by the vendor. The user may construct a database and set the database on an external network, and the host management system may authorize access to the database from a plurality of user factories.

[0092] FIG. 8 is a view showing the concept of the overall system of this embodiment that is cut out at a different angle from FIG. 7 . In the above example, a plurality of user factories having manufacturing apparatuses and the management system of the manufacturing apparatus vendor are connected via an external network, and production management of each factory or information about at least one manufacturing apparatus is communicated via the external network. In the example of FIG. 8, a factory having manufacturing apparatuses provided by a plurality of vendors and the management systems of the vendors for these manufacturing apparatuses are connected via the external network of the factory, and maintenance information of each manufacturing apparatus is communicated. In FIG. 8 , reference numeral 1201 denotes a manufacturing factory of a manufacturing apparatus user (semiconductor device manufacturer). Manufacturing apparatuses for various processes, e.g., an exposure apparatus 1202 , resist processing apparatus 1203 , and film formation apparatus 1204 are installed in the manufacturing line of the factory. FIG. 8 shows only one manufacturing factory 1201 , but a plurality of factories are networked in practice. The respective apparatuses in the factory are connected to each other by a LAN 1206 to build an intranet, and a host management system 1205 manages the operation of the manufacturing line.

[0093] The offices of vendors (apparatus supply manufacturers) such as an exposure apparatus manufacturer 1210 , resist processing apparatus manufacturer 1220 , and film formation apparatus manufacturer 1230 comprise host management systems 1211 , 1221 , and 1231 for executing remote maintenance for the supplied apparatuses. Each host management system has a maintenance database and a gateway for an external network, as described above. The host management system 1205 for managing the apparatuses in the manufacturing factory of the user, and the management systems 1211 , 1221 , and 1231 of the vendors for the respective apparatuses are connected via the Internet or dedicated network serving as an external network 1200 . In this system, if a trouble occurs in any one of the manufacturing apparatuses along the manufacturing line, the operation of the manufacturing line stops. This trouble can be quickly solved by remote maintenance from the vendor of the apparatus in trouble via the Internet 1200 . This can minimize the stop of the manufacturing line.

[0094] Each manufacturing apparatus in the semiconductor manufacturing factory comprises a display, a network interface, and a computer which executes network access software and apparatus operating software which are stored in a storage device. The storage device is a built-in memory, hard disk, or network file server. The network access software includes a dedicated or general-purpose web browser, and provides a user interface with a window as shown in FIG. 9 on the display. While referring to this window, the operator who manages manufacturing apparatuses in each factory inputs, into input fields on the windows, pieces of information such as the model of manufacturing apparatus 1401 , serial number 1402 , subject of trouble 1403 , data of occurrence of trouble 1404 , degree of urgency 1405 , symptom 1406 , remedy 1407 , and progress 1408 . The pieces of input information are transmitted to the maintenance database via the Internet, and appropriate maintenance information is sent back from the maintenance database and provided on the display. The user interface provided by the web browser realizes hyperlink functions 1410 to 1412 , as shown in FIG. 9 . This allows the operator to access more detailed information of each item, download the latest-version software to be used for a manufacturing apparatus from a software library provided by a vendor, and download an operation guide (help information) as a reference for the operator in the factory. The maintenance information provided from the maintenance database includes information about the present invention described above. The software library also provides the latest-version software for implementing the present invention.

[0095] A semiconductor device manufacturing process using the above-described production system will be explained. FIG. 10 shows the flow of the whole manufacturing process of the semiconductor device. In step 1 (circuit design), a semiconductor device circuit is designed. In step 2 (mask formation), a mask having the designed circuit pattern is formed. In step 3 (wafer formation), a wafer is formed by using a material such as silicon. In step 4 (wafer process) called a pre-process, an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. Step 5 (assembly) called a post-process is the step of forming a semiconductor chip by using the wafer formed in step 4 , and includes an assembly process (dicing and bonding) and packaging process (chip encapsulation). In step 6 (inspection), the semiconductor device manufactured in step 5 undergoes inspections such as an operation confirmation test and durability test. After these steps, the semiconductor device is completed and shipped (step 7 ). For example, the pre-process and post-process are performed in separate dedicated factories, and each of the factories receives maintenance by the above-described remote maintenance system. Information for production management and apparatus maintenance is communicated between the pre-process factory and the post-process factory via the Internet or dedicated network.

[0096] FIG. 11 shows the detailed flow of the wafer process. In step 11 (oxidation), the wafer surface is oxidized. In step 12 (CVD), an insulating film is formed on the wafer surface. In step 13 (electrode formation), an electrode is formed on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted in the wafer. In step 15 (resist processing), a photosensitive agent is applied to the wafer. In step 16 (exposure), the above-mentioned exposure apparatus exposes the wafer to the circuit pattern of a mask, and prints the circuit pattern on the wafer. In step 17 (developing), the exposed wafer is developed. In step 18 (etching), the resist is etched except for the developed resist image. In step 19 (resist removal), an unnecessary resist after etching is removed. These steps are repeated to form multiple circuit patterns on the wafer. A manufacturing apparatus used in each step undergoes maintenance by the remote maintenance system, which prevents a trouble in advance. Even if a trouble occurs, the manufacturing apparatus can be quickly recovered. The productivity of the semiconductor device can be increased in comparison with the prior art.

[0097] According to the preferred embodiment of the present invention, since the temperature of the substrate such as the wafer loaded into the process chamber of the apparatus via the load-lock chamber reaches the predetermined temperature at the time of loading, the substrate can be immediately processed, e.g., subjected to exposure, thereby improving the throughput. In particular, the larger effect can be attained in the apparatus with the evacuated chamber.

[0098] As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.