PREFERRED MODE OF THE INVENTION

[0042] Hereinafter, an embodiment in accordance with the present invention will be explained in detail based on the drawings. FIG. 1 is a partial cutaway perspective view showing an embodiment of the load port in accordance with the present invention, provided with an embodiment of the wafer mapping device in accordance with the present invention, FIG. 2 is a partial cutaway side view of a wafer treatment device provided with the load port of that embodiment, FIG. 3 is a cross sectional view of the wafer treatment device seen from above along the line B-B of FIG. 2 , and FIG. 4 is a perspective view showing the wafer mapping device of, the above embodiment, the same parts in these drawings as in the prior art example shown in FIGS. 23 and 24 being indicated by the same reference numerals.

[0043] As shown in FIGS. 1 to 3 , the wafer treatment device therein, similarly to the prior art example shown in FIGS. 23 and 24 , is a mini-environment system provided with a high cleanliness area called a mini-environment inside a cover 10 by surrounding and separating a section where a wafer conveying robot 6 and wafer processing device 8 are located and providing a fan filter unit 30 to the section, and equipped with the load port 12 of the above embodiment, which is a wafer extraction/insertion device, at the interface between the high cleanliness area and the middle or low cleanliness area wherein the clean container 2 presents, and as well as a normal control device having a micro computer, not shown in the drawings, being provided for each of the wafer conveying robot 6 and the load port 12 , a normal control device 7 having a microcomputer is provided as a superior control device for controlling these control devices.

[0044] The load port 12 of the above embodiment, similarly to the that shown in FIGS. 23 and 24 except for the structure of the wafer mapping device, as well as having a frame 31 for supporting the fan filter unit 30 and having a stage 1 outside the frame 31 , is provided on the stage 1 with a stand 3 on which the closed type clean container (FOUP) 2 as shown in FIG. 20 is mounted, and within the stage 1 a normal linear motion mechanism 9 is provided as a container main body reciprocatingly moving means or advancing/acting the stage 3 together with the container main body 2 a of the clean container 2 mounted thereon with respect to the window frame 31 a of the frame 31 .

[0045] A port door 13 , L-shaped in vertical section, is located inside the window frame 31 a of the frame 31 , and in order to force contact and elevate the front door 2 a of the clean container 2 and the port door 13 , a port door elevating mechanism 16 for elevating the port door 13 is provided as port door elevating means in the stage 1 . The port door elevating mechanism 16 , similarly to that shown in FIGS. 23 and 24 , has a motor 16 a, a ball screw 16 b rotatably supported at both end portions in an attitude where its axis extends vertically and rotated by the motor 16 a via a pulley belt transmission medial, a ball nut 16 c screwed to the screw 16 b and elevated up and down by the rotation of the screw 16 b, a bracket 17 with a horizontal C-shaped cross section as shown in FIG. 4 fixed to the ball nut 16 c , and a coupling member 18 for positioning the port door 13 above the bracket 17 and integrally fixing the pore door 13 to the bracket 17 as shown in FIG. 4 .

[0046] The load port 12 of the above embodiment also has, in the port door 13 , as a front door detachably fixing means, a registration pin 13 a for positioning the front door 2 a of the clean container 2 , a latch key 13 b for lock releasing by retraction of a latch 2 e (refer to FIG. 20 ) of the front door 2 a and reloading with the contain main body 2 b by protrusion of the latch 2 e , and an absorption pad 13 c for absorption fixing of the font door 2 a, the latch key 13 b being driven and rotated by a rotating mechanism, not shown, with an air cylinder or the like built into the port door 13 as a drive source and the adsorption pad 13 c performing attachment and release of the front door 2 a by connection to a negative pressure source, not shown and release thereof.

[0047] In the load port 12 , the wafer mapping device of the above embodiment, as shown in FIG. 4 , as well as having a C-shaped swinging frame 22 as a swinging member, fixed with a spindle 23 under the part door 13 extending parallel to the port door 13 with a horizontal axis C as a central axis, and the swinging fame 22 being positioned near the port door 13 surrounding both side surfaces and the top end surface thereof, ha a C-shaped sensor plate 21 fixed to the upper end portion of the swinging fame 22 , and a pair of sensor portions 20 are provided by means of two arm portions separated from each other, protruding from the swinging frame 22 toward the stage 3 and consequently the clean container 2 mounted thereon, while at the tip portions of these sensor portions 20 a normal light emitting device 20 a and light receiving device 20 b for recognizing wafers 4 are fixed facing each other. Also, the above spindle 23 is rotatably supported on the port door fixing bracket 17 via bearings 24 , the swinging frame 22 being thereby swingably connected to the port door 13 around the horizontal axis C.

[0048] The wafer mapping device of the above embodiment has, also fixed to the bracket 17 so as to be positioned below the spindle 23 , an air cylinder 25 as a swinging drive means, and a rod end 25 a of the air cylinder 25 abuts the lower portion of a lever 26 fixed to the spindle 23 . Further, an L-shaped stopper member 27 that engages with the lower end of the lever 26 is provided protruding from the bracket 17 in order to restrict the tilt angle of the swinging frame 22 and consequently the amount by which the sensor portions 20 enter the inside of the clean container 2 , and a damper 28 that utilizes a spring or fluid pressure is provided in the stopper member 27 to reduce to a minimum vibrations due to bumping of the lower end portion of the lever 26 . Also, a continuously energizing return spring not shown in the drawings is provided facing the vertical starting point of the swinging same 22 .

[0049] Further, in the load port of the above embodiment, a partition plate 16 d having two vertical channel portions fox housing the coupling member 18 in the example shown in the drawing so that it is vertically movable is provided on the side surface of the window fame 31 a of the frame 31 facing to the wafer conveying robot 6 , as shown in FIGS. 2 and 3 , and FIG. 17 described later. Because the linear motion mechanism 9 for reciprocally moving the clean container 2 , the port door elevating mechanism 16 , and the spindle 23 of the swinging frame 22 , which are movable portions that tend to generate contaminants, are all installed outside the mini-environment, which is the positive pressure high cleanliness area at the boundary of the partition plate 16 d and the port door 13 , even if contaminants are generated by these movable portions those contaminants are not carried into the mini-environment. Also, because the above-described rotating mechanism for rotating the latch key 13 b and rocking/releasing the latch 2 e, which is also a movable portion, as shown in FIG. 6 described hereafter, is housed inside the thickness of the port door 13 provided with a rear cover 13 d on the side facing the mini-environment, even if contaminants are generated those contaminants are not carried into the Ode of the mini-environment.

[0050] Here, explaining another characteristic of the load port of the above embodiment, in this load port, by daring to provide gaps between the port door 13 and the swinging frame 22 , between the port door 13 and the window frame 31 a of the frame 31 , and between the clean container 2 and the window frame 31 a of the fame 31 , the high cleanliness air flow from the mini-environment as positive pressure high cleanliness area is expelled to the outside, accumulation of contaminants generated by the above movable portions, even if only a little, and intrusion of contaminants from the outside to the interior of the mini-environment is prevented, and the extremely high cleanliness inside the min-environment can thereby be ensured.

[0051] In the wafer mapping device of the above embodiment, during the wafer mapping operation described later, the swinging frame 22 , as shown in FIG. 5 , swings around the horizontal axis C with the spindle 23 as a fulcrum between a mapping position tilted at 4 e toward the wafers 4 inside the clean container (FOUP) 2 on the left hand side of the drawing and a vertical staring position on the right hand side of the drawing by means of the cooperation of the reciprocal movements of the rod end 25 a of the air cylinder 25 that acts as a swinging drive means and the energizing force of the return spring.

[0052] Further, in the wafer mapping device of the above embodiment, as shown in FIGS. 1 to 3 , a light emitting device 15 a and light receiving device 15 b are provided as protrusion detecting means to detect the existence of the wafers 4 and other objects projecting from the container main body 2 a of the clean container 2 to the outside, and in this embodiment, the light emitting device 15 a is fixed facing downward in the central portion of the upper portion (head fame portion) of window frame 31 a of the frame 31 , and the light receiving device 15 b is fixed facing upward in the central portion of the lower portion of port door 13 , opposite the light emitting device 15 a . The light emitting device 15 a can also be fixed to the upper portion of the port door 13 , or the light receiving deice 15 b can also be fixed to another member adjacent to the lower portion of the port door 13 . Further, as well as fixing the light emitting device 15 a to the lower portion of the port door 13 or another member adjacent thereto, the light receiving device 15 b can be fixed to the central portion of the upper portion (head frame portion) of the window frame 31 a of the fame 31 or the upper portion of the port door 13 .

[0053] In the device concerned, as shown in FIG. 6 , when wafers 4 a or other objects projecting from the container main body 2 a block the light path from the light emitting device 15 a to the light receiving device 15 b, the light receiving device 15 b detects the object projecting from the container main body 2 a as an obstacle and outputs a light shielding signal, the light shielding signs is transmitted from the light receiving device 15 b to the superior control device 7 , and the control device 7 performs a process such as an emergency stop or the like to prevent damage to the protruding wafer 4 a, load port 12 , container main body 2 a of the clean container 2 , and the like.

[0054] FIG. 7 and FIG. 8 are perspective drawings each showing another embodiment with differing swinging drive means for the wafer mapping device of the present invention. In the example shown in FIG. 7 the driving power of the motor 34 is ted to the spindle 23 via a pulley-belt transmission reduction mechanism consists of pulleys 35 and a belt 36 , and in the example shown in FIG. 8 the driving power of the motor 34 is transmitted to the spindle 23 via a pulley-belt transmission reduction mechanism consists of pulleys 35 and a belt 36 and a cam mechanism formed by a cam 37 and the lever 26 .

[0055] FIG. 9 and FIG. 10 are perspective drawings each showing yet another embodiment with differing swinging members as well as differing swinging drive means for the wafer mapping device of the present invention, either one of the example shown in FIG. 9 and the example shown in FIG. 10 having a solenoid 38 for reciprocally moving a plunger 38 a by means of an excitation force as the swinging drive means, while in the example shown in FIG. 9 two swung rods 39 are located at the rear surf side of the port door 13 and fixed to the spindle 23 at both side portions of the lever 26 as swinging members, and the solenoid 38 swings the two swinging rods 39 by swinging the lever 26 wit the cooperation of a plunger 38 a and the return spying in the example shown in FIG. 10 a rectangular swinging frame 40 is supported via bearings by two spindles 41 protruding outward so as to be positioned on the horizontal axis C on the bracket 17 as a swinging member, and the solenoid 38 swings the entire swinging frame 40 wound the horizontal axis C by swinging the lower portion 40 a of the swinging frame 40 with the cooperation of the plunger 38 a and the return spring.

[0056] Incidentally, the swinging drive means in the wafer mapping device of the present invention is not limited to these, and in addition thereto, a means utilizing a combination conceivable by those skilled in the art, such as cylinders, solenoids, motors, pulleys, belts, cams, springs, piezo elements, dampers utilizing fluid pressure, and the like are acceptable. Also, the swinging member in the wafer mapping device of the present invention is not limited thereto and, as shown in FIG. 11 for example, can be provided with a spindle 23 at its lower end and made in an L-shape as seen from the side, its central portion being energized by an air cylinder 25 or the like as a swing drive means.

[0057] In the example of FIG. 11 , during the wafer mapping operation described later, the swinging frame 22 that serves as the swinging member swings around the horizontal axis C with the spindle 23 as a fulcrum between a mapping position rotated at α° toward the wafers 4 inside the clean container (FOUP) 2 on the left band side of the drawing and a sa position on the right hand side of the drawing by means of the cooperation of the reciprocal movements of the rod end 25 a of the air cylinder 25 that act as a swinging drive means and the energizing farce of the return spring.

[0058] Next, the track of the sensor portion 20 during the wafer mapping operation of the wafer mapping device of each of the above embodiments will be explained with reference to FIGS. 5, 6 , and 11 . During the wafer mapping operation, as shown in FIGS. 5 and 11 , by tilting the swinging frame 22 or 40 , or the swinging rods 39 α° toward the clean container (FOUP) 2 side with the spindle 23 as a fulcrum the tip portions of the sensor 20 are inserted into the inside of the container main body 2 b of the clean container 2 and the light emitting device 20 a and light receiving device 20 b, not shown here in the drawings, fixed to the tip portions of the sensor 20 are moved to a position where wafers 4 inside the container main body 2 b can be detected. The light emitting device 20 a and light receiving device 20 b of the tip portions of the sensor 20 are thereby moved from a staying position POS 10 to a detection commencement position POS 11 toward the container main body 2 b in a Y axis direction by a disuse L descending by a height of H 1 in the Z axis direction. The upper half of FIG. 6 shows the light emitting device 20 a of the sensor 20 in the starting position POS 10 , while the lower half of FIG. 6 shows the light receiving device 20 b of the sensor portion 20 in the detection commencement position POS 11 .

[0059] FIG. 6 also shows a case where the wafer 4 a protruding from the container main body 2 a blocks the light path from the light emitted device 15 a to the light receiving device 15 b, and when the wafer 4 a protrudes toward the port door 13 side (right had side in the drawing past the boundary line D, because the light receiving device 15 b outputs a signal indicating the existence of the wafer 4 a due to the reduction in the received light amount, as described previously interference between the port door 13 and the front door 2 a or the like tightly contacted thereto, and the wafer 4 a accompanying elevation of the port door 13 can be prevented beforehand.

[0060] Next, the wafer mapping operation of the wafer mapping device of the above embodiments based on the operation of the control device for the load port 12 will be explained with reference to the vertical ross sectional views of FIG. 12A to FIG. 12D , and FIG. 13A and FIG. 13B , the horizontal cross sectional views of FIG. 15A to FIG. 15C , and FIG. 16A to FIG. 16C , and the flowchart of FIG. 18 , using the first embodiment as a representative (the other embodiments operate in the same manner). Firstly, the clean container (FOUP) 2 is mounted on the stage 3 of the load port 12 ( FIG. 12A and FIG. 1S A). Al this time the port door 13 is in the uppermost position POS 0 , the swinging frame 22 is in a vertical attitude, and the light emitting device 20 a and light receiving device 20 b are in the start position POS 10 shown in FIG. 5 .

[0061] Thereafter, in step Si of FIG. 18 the control device, by operating the linear motion mechanism 9 , moves forward the stage 3 together with the clean container 2 thereon in the direction of the port door 13 . At this time, the registration pin 13 a and latch key 13 b of the front surface of the port door 13 are respectively inserted in the registration pin hole 2 c and latch key hole 2 d of the front door 2 a of the lean container 2 , and the port door 13 is fixed in a state where the front door 2 a is tightly contacted to the port door 13 by means of the absorption pad 13 c of the port door 13 ( FIG. 12B and FIG. 15B ). Next, in step S 2 , the lock of the front door 2 a by the latch 2 c is released by rotating the latch key 13 b in the latch key hole 2 d.

[0062] Subsequently, the above control device, in step S 3 , retracts the stage 3 to a standby position together with the container main body 2 b of the clean container 2 thereon by operating the above linear motion mechanism 9 ( FIG. 12C and FIG. 15C ), and in the following step S 4 , whether there is a wafer 4 a or any other obstacle that protrudes from the inside of the container main body 2 b at the standby position is determined from a signal from the light receiving device 15 b, in the bottom central portion of the port door 13 , that receives light from the light emitting device 15 a fixed to the top central portion of the window fame 31 a of the frame 31 . And if a wafer 4 a protrudes or there is another obstacle, the control device in step S 5 transmits the abnormal situation to a superior control device 7 so as to prevent damaging of a wafer and maintain the device, and the superior control device 7 that receives the abnormal situation information performs a procedure such as emergency stopping the load port 12 , wafer conveying robot 6 , and processing device 8 in step S 6 .

[0063] On the other hand, if in the above step S 4 the light receiving device 15 b has not detected a wafer 4 a or other obstacle within the range of movement of the port door, by the control of the above control device the port door 13 is lowered to the position POS 1 in step S 7 , then in step S 8 by the control of the control device the swinging frame 22 is inclined α° toward the container main body 2 b in the standby position, and the light emitting device 20 a and lift receiving device 20 b at the tips of the sensor portion 20 are inserted in the container main body 2 b and moved to the detection commencement position POS 11 ( FIG. 12D and FIG. 16A ).

[0064] Subsequently the above control device, in step S 9 , lowers the port door 13 from the position POS 1 to the position POS 2 , lowers the light emitting device 20 a and light receiving device 20 b at the tips of the sensor portion 20 from the detection commencement position POS 11 to the detection completion position POS 12 by the height H 2 via the swinging frame 22 as shown in FIG. 5 , determines during that interval, in step S 10 , whether they have descended to the detection completion position POS 12 and mapping has been completed, and if not, in step 11 detects the wafers 4 by means of the light receiving device 20 b and in step 12 stores the wafer detection position in the relevant control device and repeats the process. In other words, based on changes in the output signal of the light receiving device 20 b generated by intermittent blocking of the light path between the light emitting device 20 a and the light receiving device 20 b by wafers 4 accompanying the lowering of the sensor portion 20 , as well as recognizing that the wafers 4 are housed in the container main body 2 b, it stores position information (position on the Z axis) of the port door 13 when the light path is blocked.

[0065] On the other hand, in step S 10 , as shown in FIG. 13A and FIG. 16B as well as FIG. 17 , if it is determined that the light emitting device 20 a and light receiving device 20 b at the tips of the sensor portion 20 have descended to the detection completion position POS 12 and mapping has concluded, the above control device returns the swinging frame 22 , inclined at α°, to a vertical attitude and returns the light emitting device 20 a and light device 20 b at the tips of the sensor portion 20 to the starting position apart from the container main body 2 b in the Y axis direction in step S 13 .

[0066] Then the control device, in step S 14 , transmit to the superior control device 7 the position information of the port door 13 when the light path between the light emitting device 20 a and light receiving device 20 b is blocked by the wafers 4 . The superior control device 7 can thereby obtain information concerning which shelves among the plurality of shelves inside the container main body 2 b the wafers 4 are mounted and stored on, information on whether there are wafers 4 housed in the container main body 2 b on different levels, etc, and because the superior control device 7 sends this information to the control device for the wafer conveying robot 6 and convey the wafers 4 inside the container main body 2 b, slipping wasted conveying operations with respect to shelves in the container main body 2 b on which wafers 4 are not housed and conveying the wafers 4 by selecting specific shelves is possible.

[0067] Subsequently, the above control device, in step S 15 , lowers the port door 13 to position POS 3 as shown in FIG. 13B and FIG. 16C , and as well as lowering the light emitting device 20 a and light receiving device 20 b at the tip of the sensor portion 20 from the detection completion position POS 12 to the standby position POS 13 by a height of H 3 as shown in FIG. 5 , stores the port door 13 in the lower portion of the load port 12 , then in step S 16 , by operating the linear motion mechanism 9 , moves forward the stage 3 and, as shown in FIG. 13B , moves the container main body 2 b on the stage 3 to a wafer receiving/delivering position for the wafer conveying robot 6 . With this, the mapping operation sequence is complete.

[0068] Next, following the above mapping operation, with resect to the operation of the wafer treatment device, from carrying out of the wafers 4 by the wafer conveying robot 6 from inside of the container main body 2 b to the return of the wafers 4 to the inside of the container main body 2 b via processing of the wafers 4 by the wafer processing device 8 , based on the coordinated operations of the two subordinate control devices for the load port 12 and the wafer conveying robot 6 under the control of the superior control device 7 an explanation thereof will be given with referee to the vertical cross sectional views of FIG. 13C , FIG. 13D , FIG. 14A and FIG. 14B , the horizontal cross sectional view of FIG. 16D , and the flowchart of FIG. 19 , using the first embodiment relating to the wafer mapping device as a representative (the other embodiments operate in the same manner).

[0069] Firstly, in step S 17 of FIG. 19 the wafer conveying robot 6 control device operates the wafer conveying robot 6 to extract the wafer 4 housed in the container main body 2 b in the wafer receiving/delivering position as shown in FIG. 13C , FIG. 13D and FIG. 16D and move the wafer 4 to the interior of the wafer processing deice 8 , then in step S 18 the superior control device 7 operates the wafer processing device 8 to perform such processing as etching and the like, for example, on the wafers 4 moved to the interior of the wafer processing device 8 . Incidentally, the wafer conveying robot 6 here has a rotating arm 6 b supporting a hand 6 a and another rotating arm 6 c for supporting the rotating arm 6 b, and is able to move the hand 6 a to any position by the rotation of the rotating as 6 b and 6 c, while the wafer conveying robot of the wafer processing device provided with the load port of the present invention is not limited to this and can be polar coordinate type that moves the hand by arm rotation and extension, or a rectangular coordinate type that moves the hand by a combination of linear motion mechanisms.

[0070] Next, in step S 19 the wafer conveying robot 6 control device operates the wafer conveying robot 6 to store wafers 4 processed by the wafer processing device 8 on shelves specified by the operator of the wafer processing device inside the container main body 2 b, then in step S 20 the superior control device 7 determines whether processing by the wafer processing device 8 has finished, and if there are wafers 4 whose processing is not finished inside the container main body 2 b, returns to step S 17 , while if processing by the wafer processing device 8 has finished, in step S 21 the load port 12 control device the stage 3 by operating the linear motion mechanism 9 , thereby retracting the container main body 2 b to the standby position as shown in FIG. 12D and FIG. 16C .

[0071] Subsequently, the load port 12 control device in step S 22 , raises the port door 13 in position POS 3 to position POS 0 (starting position) as shown in FIG. 14A , then in step S 23 moves forward (extends) the stage 3 by opening the linear motion mechanism 9 to extend the port door 13 toward the container main body 2 b and engage and make tightly contact the container main body 2 b and the front door 4 a tightly contacted to the port door 13 , and subsequently in step S 24 locks the front door 2 a to the container main body 2 b with the latch 2 e by rotating the latch key 13 b in the opposite direction to the rotation of step S 2 in the latch key hole 2 d, and finally in step S 25 retracts the stage 3 to the staring position by operating the linear motion mechanism 9 and, as shown in FIG. 14B , rests the clean container 2 in the direction away from the port door 13 . By this means, the operation from conveyance of the wafers 4 by the wafer conveying robot 6 to the wafers being returned to the container main body 2 b of the clean container 2 via the processing of the wafers 4 by the wafer processing device 8 is completed.

[0072] Although explained based on the examples in the drawings, the preset invention is not limited to the above-described examples, and includes modifications that can be achieved by those skilled in the art within the scope of the claims.

[0073] Industrial Application

[0074] According to the present invention, as well as eliminating the possibility of intrusion into the clean container of minute contaminants, light from a light emitting device can be made continuously accurately incident on a light receiving device over long periods of operation.