A double-sided photolithography machine

Abstract

The present invention belongs to the technical field of photolithography machines, and discloses a double-sided photolithography machine, wherein a first mechanical arm is provided on a frame, and a loading station, a pre-alignment station, an exposure station and a unloading station are distributed along the circumference of the periphery of the first mechanical arm, a loading box is provided at the loading station, a pre-alignment device is provided at the pre-alignment station, a work table and an exposure mechanism are provided at the exposure station, and an unloading box is provided at the unloading station. A double-sided photolithography machine provided by the present invention realizes the transportation of silicon wafers in various stations through a mechanical arm, and after the silicon wafer is taken out from the loading box, it is first placed on the pre-alignment device to find the trimming of the silicon wafer and the preliminary centering, and then the silicon wafer is placed on the work table that has been aligned, and the exposure mechanism performs exposure, and the exposed silicon wafer is taken out and placed in the unloading box, and the above cycle is repeated to realize automated photolithography operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of photolithography machines, and in particular relates to a double-sided photolithography machine. Background Art

[0002] Photolithography is a very important process in semiconductor manufacturing. It is a process of transferring chip patterns on a series of mask plates to the corresponding layers of silicon wafers through exposure. It is considered to be the core step in large-scale integrated circuit manufacturing. A series of complex and time-consuming photolithography processes in semiconductor manufacturing are mainly completed by corresponding photolithography machines. Existing photolithography machines have a low degree of automation and require a lot of manual operation, resulting in low photolithography efficiency. Summary of the invention

[0003] The present invention aims to solve the above technical problems at least to a certain extent. To this end, the present invention aims to provide a double-sided photolithography machine.

[0004] The technical solution adopted by the present invention is:

[0005] A double-sided photolithography machine comprises a frame, a first mechanical arm is arranged on the frame, a loading station, a pre-alignment station, an exposure station and a unloading station are distributed along the circumference of the periphery of the first mechanical arm, a loading box is arranged at the loading station, a pre-alignment device is arranged at the pre-alignment station, a workpiece stage and an exposure mechanism are arranged at the exposure station, and an unloading box is arranged at the unloading station; the workpiece stage comprises an XYY platform, a lower mounting platform fixedly mounted on the XYY platform, and an upper mounting platform located above the lower mounting platform, the upper mounting platform is mounted on a lifting mechanism, an upper mask is mounted on the upper mounting platform, and a lower mask is mounted on the lower mounting platform; a first camera is arranged between the XYY platform and the lower mounting platform.

[0006] Preferably, the lower mounting platform is provided with an air blowing hole facing the upper mounting platform, and the upper mounting platform is also provided with an air blowing hole facing the lower mounting platform; the air blowing holes are all connected to a positive pressure air source, a pressure gauge is provided between the air blowing holes and the positive pressure air source, and the pressure gauge is electrically connected to the lifting mechanism.

[0007] Preferably, clamping blocks are provided on the four sides of the lower mask, and push blocks are provided on the lower mounting platform at positions opposite to the clamping blocks, wherein the push blocks at two adjacent side positions are installed on the free ends of the clamping cylinder, and the clamping cylinder is fixedly installed on the lower mounting platform.

[0008] Preferably, the first camera is mounted on an XYZ three-axis motion mechanism, which includes an X-axis linear slide, a Y-axis linear slide mounted on the free end of the X-axis linear slide, a Z-axis linear slide mounted on the free end of the Y-axis linear slide, and a mounting base mounted on the fixed end of the Z-axis linear slide, and the first camera is mounted on the mounting base.

[0009] Preferably, a second robotic arm is provided between the pre-alignment station and the exposure station, and a third robotic arm is provided between the exposure station and the unloading station.

[0010] Preferably, the second mechanical arm comprises a motor, a straight arm mounted on the free end of the motor, and a negative pressure suction cup mounted on the straight arm, wherein the negative pressure suction cup is connected to a negative pressure air source.

[0011] Preferably, the pre-alignment device includes a pre-alignment table, a first cylinder and a second cylinder are respectively provided on both sides of the pre-alignment table, a first push claw is provided on the free end of the first cylinder, and a second push claw is provided on the free end of the second cylinder; a second camera is provided above the pre-alignment table.

[0012] Preferably, a third cylinder is provided on the first push claw, a third push claw is provided on the free end of the third cylinder, a fourth cylinder is provided on the second push claw, and a fourth push claw is provided on the free end of the fourth cylinder.

[0013] Preferably, a support rod is provided on the frame, a fifth cylinder is mounted on the support rod, and the second camera is mounted on the free end of the fifth cylinder.

[0014] Preferably, a protective cover is provided on the periphery of the frame, and an inspection door is provided on the protective cover.

[0015] The beneficial effects of the present invention are:

[0016] A double-sided photolithography machine provided by the present invention realizes the transfer of silicon wafers between various workstations through a robotic arm. After the silicon wafer is taken out from the loading box, it is first placed in a pre-alignment device to find the cutting edge of the silicon wafer and preliminary centering, and then the silicon wafer is placed on the aligned workpiece table, and the exposure mechanism performs exposure. The exposed silicon wafer is taken out and placed in the unloading box, and the above cycle is repeated to realize automated photolithography operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of the protective cover of the present invention.

[0018] Figure 2 It is a three-dimensional diagram of the double-sided photolithography machine of the present invention.

[0019] Figure 3 It is a top view of the double-sided photolithography machine of the present invention.

[0020] Figure 4 It is a schematic structural diagram of the second mechanical arm of the present invention.

[0021] Figure 5 It is a structural schematic diagram of the pre-alignment device of the present invention.

[0022] Figure 6 It is a structural schematic diagram of the workpiece platform of the present invention.

[0023] Figure 7 It is a structural schematic diagram of the workpiece platform of the present invention from another angle.

[0024] Figure 8 It is a structural schematic diagram of the lower mounting platform of the present invention.

[0025] In the figure: 1-frame; 2-first mechanical arm; 3-loading box; 4-pre-alignment device; 401-pre-alignment table; 402-first cylinder; 403-first push claw; 404-second camera; 405-third cylinder; 406-third push claw; 407-support rod; 408-fifth cylinder; 5-workpiece table; 501-XYY platform; 502-lower mounting table; 503-upper mounting table; 504-lifting mechanism; 505-upper mask; 506-second camera; 507-support rod; 508-fifth cylinder; 509-XYY platform; 510-XYY platform; 511-XYY platform; 512-lower mounting table; 513-upper mounting table; 514-lifting mechanism; 515-upper mask; 516-XYY platform; 517-XYY platform; 518-XYY platform; 519-XYY platform; 520-XYY platform; 521-XYY platform; 522-XYY platform; 523-XYY platform; 524-XYY platform; 525-XYY platform; 526-XYY platform; 527-XYY platform; 528-XYY platform; 529-XYY platform; 530-XYY platform; 531-XYY platform; 532-XYY platform; 533-XYY platform; 534-XYY platform; 535-XYY platform; 536-XYY platform; 537-XYY platform; 538-XYY platform; 539-XYY platform; 540-XYY platform; 541-XYY platform; 6-lower mask; 507-first camera; 508-blowing hole; 509-pressing block; 510-pushing block; 511-pressing cylinder; 512-X-axis linear slide; 513-Y-axis linear slide; 514-Z-axis linear slide; 515-mounting seat; 6-exposure mechanism; 7-unloading box; 8-second robotic arm; 801-motor; 802-straight arm; 803-negative pressure suction cup; 9-third robotic arm; 10-protective cover; 11-inspection door. DETAILED DESCRIPTION

[0026] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention. The components of the embodiments of the present invention generally described and shown in the drawings herein may be arranged and designed in a variety of different configurations.

[0027] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or position relationship is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invented product is usually placed when in use, or the orientation or position relationship commonly understood by those skilled in the art, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention and the drawings in the embodiments can be understood in specific circumstances, and the technical solutions in the embodiments of the present invention can be clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments.

[0029] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0030] like Figures 1 to 8 As shown, a double-sided lithography machine of the present embodiment comprises a frame 1, on which a first robot arm 2 is provided, and a loading station, a pre-alignment station, an exposure station and an unloading station are distributed clockwise along the circumferential direction on the periphery of the first robot arm 2, two loading boxes 3 are provided at the loading station, a pre-alignment device 4 is provided at the pre-alignment station, a workpiece table 5 and an exposure mechanism 6 are provided at the exposure station, and the exposure mechanism 6 is located above the workpiece table 5, and two unloading boxes 7 are provided at the unloading station; a second robot arm 8 is provided between the pre-alignment station and the exposure station, and a third robot arm 9 is provided between the exposure station and the unloading station.

[0031] Silicon wafers of the same specification are stacked in the loading box 3. After the first robot arm 2 takes out the silicon wafer, it is first placed in the pre-alignment device 4. The pre-alignment device 4 is used to find the cutting edge of the silicon wafer and the preliminary centering. Then the second robot arm 8 places the silicon wafer on the aligned workpiece table 5, and the exposure mechanism 6 performs exposure. The exposed silicon wafer is taken out by the third robot arm 9, and finally the first robot arm 2 places the silicon wafer into the unloading box 7. The above is a working cycle of the double-sided lithography machine. Repeating the above cycle can realize automated lithography operations.

[0032] In order to realize double-sided lithography, the workpiece stage 5 includes an upper mask plate 505 and a lower mask plate 506. Specifically, the workpiece stage 5 also includes an XYY platform 501, a lower mounting table 502, an upper mounting table 503 and a lifting mechanism 504. The lower mounting table 502 is fixedly mounted on the XYY platform 501, the upper mounting table 503 is located above the lower mounting table 502, the upper mounting table 503 is mounted on the lifting mechanism 504, the upper mask plate 505 is mounted on the upper mounting table 503, and the lower mask plate 506 is mounted on the lower mounting table 502; a first camera 507 is provided between the XYY platform 501 and the lower mounting table 502.

[0033] The XYY platform 501, the exposure mechanism and the lifting mechanism 504 are all prior art, and the image recognition of the camera is also prior art.

[0034] The lower mounting platform 502 is provided with a plurality of air blowing holes 508 facing the upper mounting platform 503 . The air blowing holes 508 are connected to a positive pressure air source. A pressure gauge is provided between the air blowing holes 508 and the positive pressure air source. The pressure gauge is electrically connected to the lifting mechanism 504 .

[0035] The upper mounting platform 503 is also provided with air blowing holes facing the lower mounting platform 502 , and the air blowing holes of the upper mounting platform 503 are arranged in one-to-one correspondence with the air blowing holes of the lower mounting platform 502 .

[0036] The XYY platform 501 is automatically leveled first, and then the upper mounting platform 503 is moved downward to fit with the lower mounting platform 502 under the action of the lifting mechanism 504. During the descent of the upper mounting platform 503, the air holes blow air outward. At this time, the air pressure monitored by the barometer is normal. When the upper mounting platform 503 and the lower mounting platform 502 are fitted together, the air holes of the upper mounting platform 503 and the air holes of the lower mounting platform 502 correspond to each other, resulting in that the gas cannot be blown out smoothly. At this time, the air pressure monitored by the barometer increases. When it reaches the preset value, the lifting mechanism 504 stops moving, which means that the upper mounting platform 503 and the lower mounting platform 502 are already fitted together.

[0037] After the bonding, the first camera 507 is used to identify the alignment of the upper mask 505 and the lower mask 506. If the alignment is not successful, the lower mounting platform 502 is fine-tuned through the XYY platform 501 until the first camera 507 recognizes that the upper mask 505 and the lower mask 506 are successfully aligned. After the alignment is successful, the lifting mechanism 504 drives the upper mask 505 to rise, and the second mechanical arm 8 puts the silicon wafer on the lower mask 506. After the second mechanical arm 8 is retracted, the lifting mechanism 504 drives the upper mask 505 to descend again and clamps the silicon wafer with the lower mask 506 for exposure (the stroke of this descent is the height of the first descent minus the thickness of the silicon wafer, and the thickness of the silicon wafer is a preset value according to the silicon wafer model). After the exposure is completed, the lifting mechanism 504 drives the upper mask 505 to rise again, and the third mechanical arm 9 extends to take out the silicon wafer.

[0038] It should be noted that in actual applications, it is not necessary to align the upper mask 505 and the lower mask 506 every time. Since silicon wafers are standard parts with uniform specifications, it is sufficient to perform one alignment and then perform another alignment for correction after exposing multiple silicon wafers.

[0039] The four sides of the lower mask 506 are provided with clamping blocks 509, and the lower mounting platform 502 is provided with push blocks 510 at positions opposite to the clamping blocks 509, wherein the push blocks 510 at two adjacent side positions are installed on the free ends of the clamping cylinder 511, and the clamping cylinder 511 is fixedly installed on the lower mounting platform 502. When the clamping cylinder 511 is pushed out, the push blocks act to fix the lower mask 506 on the lower mounting platform 502. Similarly, when the clamping cylinder 511 is retracted, the push blocks are released, and the lower mask 506 can be removed. The upper mask 505 is also provided with the same detachable arrangement on the upper mounting platform 503.

[0040] The first camera 507 is mounted on an XYZ three-axis motion mechanism. In order to ensure the accuracy of image recognition of the first camera 507, the position of the first camera 507 can be accurately adjusted through the XYZ three-axis motion mechanism. The XYZ three-axis motion mechanism includes an X-axis linear slide 512, a Y-axis linear slide 513 mounted on the free end of the X-axis linear slide 512, a Z-axis linear slide 514 mounted on the free end of the Y-axis linear slide 513, and a mounting seat 515 mounted on the fixed end of the Z-axis linear slide 514. The first camera 507 is mounted on the mounting seat 515. The first camera 507 can be adjusted in the X-axis direction, the Y-axis direction and the Z-axis direction respectively through the X-axis linear slide 512, the Y-axis linear slide 513 and the Z-axis linear slide 514.

[0041] The second robotic arm 8 includes a motor 801, a straight arm 802 mounted on the free end of the motor 801, and a negative pressure suction cup 803 mounted on the straight arm 802, and the negative pressure suction cup 803 is connected to a negative pressure gas source. After the negative pressure suction cup sucks the silicon wafer, the motor 801 drives the straight arm 802 to rotate a set angle to realize the transportation of the silicon wafer. The structure of the third robotic arm 9 is the same as that of the second robotic arm 8. In order to facilitate the transportation of the silicon wafer by the first robotic arm 2, a temporary supporting platform for placing the silicon wafer is provided under the third robotic arm 9. Compared with the first robotic arm 2, the second robotic arm 8 and the third robotic arm 9 can realize the transportation of silicon wafers along the arc direction faster and more smoothly.

[0042] The pre-alignment device 4 includes a pre-alignment table 401, and a first cylinder 402 and a second cylinder are symmetrically arranged on both sides of the pre-alignment table 401, a first push claw 403 is arranged on the free end of the first cylinder 402, and a second push claw is arranged on the free end of the second cylinder, and the first push claw 403 and the second push claw are arranged opposite to each other; a second camera 404 is arranged above the pre-alignment table 401.

[0043] The first push claw 403 is provided with a third cylinder 405, a third push claw 406 is provided on the free end of the third cylinder 405, the second push claw is provided with a fourth cylinder, a fourth push claw is provided on the free end of the fourth cylinder, and the third push claw 406 and the fourth push claw are arranged oppositely.

[0044] The first push claw 403, the second push claw, the third push claw 406 and the fourth push claw are all arc-shaped at one end facing the alignment table 401. When in use, the third cylinder 405 drives the third push claw 406 to descend, and the fourth cylinder drives the fourth push claw to descend, so that the third push claw 406 and the fourth push claw are opposite to each other, and the positions of the third push claw 406 and the fourth push claw are ensured to be lower than the positions of the first push claw 403 and the second push claw. When the first cylinder 402 and the second cylinder are started, the third push claw 406 and the fourth push claw are close to each other, the first push claw 403 and the second push claw are close to each other, the third push claw 406 and the fourth push claw are in contact with both sides of the pre-alignment table 401, and the first push claw 403 and the second push claw are in contact with both sides of the silicon wafer, thereby pushing the center of the silicon wafer to overlap with the center of the pre-alignment table 401, and then the second camera 404 identifies the position of the silicon wafer.

[0045] The frame 1 is provided with a support rod 407, on which a fifth cylinder 408 is mounted, and the second camera 404 is mounted on the free end of the fifth cylinder 408. The telescopic movement of the fifth cylinder 408 can adjust the position of the second camera 404 to ensure that the second camera 404 is placed directly on the pre-alignment table 401. When the center of the silicon wafer overlaps with the center of the pre-alignment table 401, the second camera 404 performs image recognition to find the cut edge of the silicon wafer, and then the second robot arm 8 places the silicon wafer accurately on the workpiece table 5.

[0046] A protective cover 10 is disposed on the periphery of the frame 1, and the protective cover 10 protects the double-sided lithography machine as a whole. A plurality of inspection doors 11 are disposed on the protective cover 10 for easy inspection and maintenance.

[0047] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A double-sided photolithography machine, characterized in that: The invention comprises a frame (1), a first mechanical arm (2) is arranged on the frame (1), a loading station, a pre-alignment station, an exposure station and a unloading station are arranged along the circumference of the periphery of the first mechanical arm (2), a loading box (3) is arranged at the loading station, a pre-alignment device (4) is arranged at the pre-alignment station, a workpiece table (5) and an exposure mechanism (6) are arranged at the exposure station, and an unloading box (7) is arranged at the unloading station; the workpiece table (5) comprises an XYY platform (501), and a lower mounting table (502) fixedly mounted on the XYY platform (501). and an upper mounting platform (503) located above the lower mounting platform (502), the upper mounting platform (503) being mounted on a lifting mechanism (504), an upper mask plate (505) being mounted on the upper mounting platform (503), and a lower mask plate (506) being mounted on the lower mounting platform (502); a first camera (507) being arranged between the XYY platform (501) and the lower mounting platform (502); the pre-alignment device (4) comprising a pre-alignment platform (401), and first cylinders (402) being arranged on both sides of the pre-alignment platform (401) ) and a second air cylinder, a first push claw (403) is provided on the free end of the first air cylinder (402), and a second push claw is provided on the free end of the second air cylinder; a second camera (404) is provided above the pre-alignment platform (401); a third air cylinder (405) is provided on the first push claw (403), and a third push claw (406) is provided on the free end of the third air cylinder (405); a fourth air cylinder is provided on the second push claw, and a fourth push claw is provided on the free end of the fourth cylinder; the first push claw (403), the second push claw, and the third push claw (406) ) and one end of the fourth push claw facing the alignment platform (401) are both arc-shaped. When in use, the positions of the third push claw (406) and the fourth push claw are lower than the positions of the first push claw (403) and the second push claw. The third push claw (406) and the fourth push claw are close to each other, the first push claw (403) and the second push claw are close to each other, the third push claw (406) and the fourth push claw are in contact with both sides of the pre-alignment platform (401), and the first push claw (403) and the second push claw are in contact with both sides of the silicon wafer, so that the center of the silicon wafer is pushed to overlap with the center of the pre-alignment platform (401).

2. The double-sided photolithography machine according to claim 1, characterized in that: The lower mounting platform (502) is provided with an air blowing hole facing the upper mounting platform (503), and the upper mounting platform (503) is also provided with an air blowing hole facing the lower mounting platform (502); the air blowing holes are both connected to a positive pressure air source, a pressure gauge is provided between the air blowing hole and the positive pressure air source, and the pressure gauge is electrically connected to the lifting mechanism (504).

3. The double-sided photolithography machine according to claim 1, characterized in that: The four side surfaces of the lower mask plate (506) are each provided with a clamping block (509), and a push block (510) is provided on the lower mounting platform (502) at a position opposite to the clamping block (509), wherein the push blocks (510) at two adjacent side positions are mounted on the free ends of a clamping cylinder (511), and the clamping cylinder (511) is fixedly mounted on the lower mounting platform (502).

4. The double-sided photolithography machine according to claim 1, characterized in that: The first camera (507) is mounted on an XYZ three-axis motion mechanism, which includes an X-axis linear slide (512), a Y-axis linear slide (513) mounted on the free end of the X-axis linear slide (512), a Z-axis linear slide (514) mounted on the free end of the Y-axis linear slide (513), and a mounting seat (515) mounted on the fixed end of the Z-axis linear slide (514), and the first camera (507) is mounted on the mounting seat (515).

5. The double-sided photolithography machine according to claim 1, characterized in that: A second mechanical arm (8) is provided between the pre-alignment station and the exposure station, and a third mechanical arm (9) is provided between the exposure station and the unloading station.

6. The double-sided photolithography machine according to claim 5, characterized in that: The second mechanical arm (8) comprises a motor (801), a straight arm (802) mounted on the free end of the motor (801), and a negative pressure suction cup (803) mounted on the straight arm (802), wherein the negative pressure suction cup (803) is connected to a negative pressure gas source.

7. The double-sided photolithography machine according to claim 1, characterized in that: The frame (1) is provided with a support rod (407), a fifth cylinder (408) is mounted on the support rod (407), and the second camera (404) is mounted on the free end of the fifth cylinder (408).

8. The double-sided photolithography machine according to any one of claims 1 to 7, characterized in that: A protective cover (10) is provided on the periphery of the frame (1), and an inspection door (11) is provided on the protective cover (10).

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