Substrate holding device, exposing device, laser processing device, and substrate holding method

Abstract

To provide a substrate holding device or the like that holds a substrate suitably in accordance with warpage of the substrate.SOLUTION: A laser processing device 100 according to this embodiment includes a lifting mechanism 90 including lifters 90A and 90B. In the lifters 90A and 90B, warpage detection sensors 92 and 94 are provided. The warpage detection sensors 92 and 94 detect the warpage at an end part of a substrate W in a process where the substrate W is placed on a table 70 and the lifters 90A and 90B then rise in order to press the substrate W from an upper surface side. Then, at the position of the warpage detection, the rise of the lifters 90A and 90B is stopped and the pressing operation, that is, the movement in a horizontal direction (Y direction) and lowering of the lifters 90A and 90B are performed.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a substrate holding device for holding a substrate, and more particularly to a substrate holding mechanism. [Background technology]

[0002] Devices that process substrates, such as exposure devices, laser processing devices, and coating devices (hereinafter referred to as semiconductor processing devices), are equipped with a mechanism for fixing a substrate carried into the device on a substrate mounting table. For example, in an exposure device, a vacuum chuck is provided on the table on which the substrate is mounted, and the substrate is attracted to and fixed to the table by vacuum suction. A laser processing device that forms vias or the like in a substrate also has a substrate holding device equipped with a vacuum chuck.

[0003] Warping occurs around the periphery of a substrate due to heat treatment, etc. In order to bring the entire warped substrate into close contact with the table, a pressing member (fixing member) is provided around the periphery of the substrate, which presses down and fixes the substrate from above (see Patent Document 1).

[0004] Furthermore, if the substrate is warped, there is a risk that the substrate may slip when placed on the table. For this reason, an inspection device is known in which a protrusion is provided on a substrate holding member, and the edge surface of the substrate comes into contact with the protrusion (see Patent Document 2). In this device, the holding member holds the bottom surface of the substrate while pressing the edge surface of the substrate with the protrusion, thereby fixing the substrate to the table. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-81156 [Patent Document 2] Japanese Patent Publication No. 2022-79225 Summary of the Invention [Problem to be solved by the invention]

[0006] Substrates processed in exposure equipment, laser processing equipment, etc. vary in size, material, strength, etc., and the degree of warping of the substrate also differs depending on the type of substrate, heat resistance, etc. Therefore, when fixing a substrate to a table, if pressure is applied to the substrate from both the top surface and edge of its peripheral edge, the load on the peripheral edge of the substrate may become excessively large.

[0007] Therefore, it is necessary to hold the substrate appropriately depending on the warpage of the substrate. [Means for solving the problem]

[0008] The substrate holding device, which is one aspect of the present invention, can be incorporated into an exposure device such as a contact exposure device, a maskless exposure device, or a projection exposure device, or can be configured as a substrate holding device that can operate in cooperation with such an exposure device, and can also be incorporated into a laser processing device or the like, or can be configured as a substrate holding device that can operate in cooperation with such an exposure device.

[0009] The substrate holding device of the present invention comprises a table, a lifting mechanism for placing a substrate on the table, a pressing member for pressing the substrate placed on the table from the peripheral edge side of the substrate, and a control unit for driving and controlling the pressing member and the lifting mechanism.

[0010] The substrate holding device of the present invention includes a warpage detection unit that detects warpage of the substrate placed on the table from the peripheral edge side of the substrate, and a control unit that drives and controls the pressing member in accordance with the warpage of the substrate. Here, the "periphery side of the substrate" includes the area facing the edge (side) of the substrate and the periphery of the edge of the substrate, but does not include the upper side of the substrate surface. The detection of warpage of the substrate may be performed using either a quantitative or non-quantitative method, as long as it is configured to acquire information that allows the control unit to make decisions on how to execute control.

[0011] The warpage detection unit can quantitatively or non-quantitatively detect the height of the substrate from the table surface when it is placed on the table. For example, the warpage detection unit includes a light-emitting unit and a light-receiving unit that are arranged opposite each other near the periphery of the table, and detects warpage of the substrate when the light-receiving unit receives light from the light-emitting unit. Alternatively, the warpage detection unit includes a light-emitting unit and a light-receiving unit that can receive light emitted from the light-emitting unit and reflected by the substrate, and detects warpage of the substrate when the light-receiving unit no longer receives reflected light.

[0012] For example, the control unit can change the position at which the pressing member starts pressing the substrate depending on the degree of warpage detected. For example, the control unit can detect the warpage of the substrate as a height from the table surface, and when the detected height or information corresponding to the height is acquired, the control unit can start the pressing operation according to that height.

[0013] The warpage detection unit can detect the warpage of the substrate by moving relatively to the substrate. For example, the warpage detection unit can be configured to move up or down with the substrate placed on a table.

[0014] The warpage detection unit can be configured to work in conjunction with the lifting mechanism. The warpage detection unit can detect the warpage of the substrate as the lifting mechanism rises. For example, if the lifting mechanism is movable along the support surface of the table and is equipped with a lifter that also serves as a pressing member, the warpage detection unit can be configured to be provided on the lifter.

[0015] A substrate holding device according to another aspect of the present invention includes a table, a lifting mechanism for placing a substrate on the table, a pressing member for pressing the substrate placed on the table from the peripheral edge side of the substrate, a control unit for driving and controlling the pressing member and the lifting mechanism, and a warpage detection unit for detecting warpage of the substrate placed on the table, wherein the control unit changes the position at which the pressing member starts pressing the substrate according to the warpage of the substrate detected by the warpage detection unit. For example, the warpage detection unit can detect warpage from the peripheral edge side of the substrate or from above the surface of the substrate.

[0016] Another aspect of the present invention is a substrate holding method that includes the steps of placing a substrate on a table, detecting the warpage of the substrate placed on the table from the peripheral edge side of the substrate, and performing a pressing operation to press down on the substrate placed on the table from the peripheral edge side of the substrate, and the starting position of the pressing operation is determined depending on the warpage of the substrate. [Effects of the Invention]

[0017] According to the present invention, in a substrate holding device or the like, a substrate can be held appropriately in accordance with the warpage of the substrate. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic configuration diagram of a laser processing device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic plan view of the substrate holding device as seen from above. [Figure 3] 10A to 10C are diagrams showing the process of placing and fixing a substrate on a table. [Figure 4] FIG. 10 is a flowchart showing a process of detecting warpage of a substrate. [Figure 5] 10A to 10C are diagrams illustrating a process for detecting warpage of a substrate. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, a laser processing apparatus equipped with a substrate holding device according to this embodiment will be described with reference to the drawings.

[0020] FIG. 1 is a schematic diagram of the laser processing device according to this embodiment.

[0021] The laser processing apparatus 100 is an apparatus for performing ablation processing, and includes a light source unit 10 and a main body 20. The light source unit 10 includes a laser 11, which in this case is configured as a KrF excimer laser with a wavelength of 248 nm. Laser light L1 is guided to the main body 20 via a beam position correction unit 12 which includes an optical system such as a mirror.

[0022] The main body 20 includes an illumination optical system 30, a projection optical system 34, a mask stage 40, and a processing stage 50. The illumination optical system 30 and the projection optical system 34 are supported by a support 22 mounted on a base 21. The illumination optical system 30 includes a lens array 30A, a line beam shaping optical system 30B, and a mirror 30C, and homogenizes the light intensity distribution of the incident laser light L1 and shapes it into a line-shaped beam. The line-shaped beam LB is guided toward the mask stage 40 by the mirror 30C.

[0023] A mask M on which a processing pattern is formed is placed on the mask stage 40. For example, the processing pattern may include through vias, blind vias, and wiring pattern grooves (trenches). The linear beam LB transmitted through the mask M is incident on the projection optical system 34 and is imaged on the substrate W placed on the processing stage 50. A plurality of pattern areas (processing areas) are regularly defined on the substrate W. Furthermore, XYZ coordinate systems that are orthogonal to each other are defined for the mask stage 40 and the processing stage 50.

[0024] The scanning mechanism 32 is connected to the casing 30F of the illumination optical system 30 so as to face it, and is capable of reciprocating movement along the X direction. The scanning mechanism 32 moves the illumination optical system 30 along the X direction, and scans the linear beam LB along the X direction, which is the scanning direction. As a result, the pattern formed on the mask M is formed in the pattern area of ​​the substrate W.

[0025] The processing stage 50 is movable along the X and Y directions. The processing stage 50 moves stepwise in the X and Y directions every time a pattern is formed in a pattern area of ​​the substrate W, thereby performing ablation processing on the entire substrate W.

[0026] The processing stage 50 is provided with a substrate holding device 60 that holds the substrate W. The substrate W is transported by a transport mechanism (not shown) and placed on the processing stage 50 by the substrate holding device 60. When the ablation processing on the substrate W is completed, the transport mechanism removes the processed substrate W and transports the next substrate W to be processed.

[0027] A control unit 25 provided in the main body 20 controls the operation of the laser processing apparatus 100 and outputs control signals to the scanning mechanism 32, the substrate holding device 60, etc. The substrate holding device 60 holds and fixes the substrate W in response to the control signal from the control unit 25.

[0028] 2 is a schematic plan view of the substrate holding device 60 as seen from above. The substrate holding device 60 will be described with reference to FIG.

[0029] The substrate holding device 60 includes a table 70, a clamping mechanism 80, and a lifting mechanism 90. The rectangular table 70 supports the substrate W on its support surface 70S and is configured as a vacuum chuck. In the center of the table 70 in the Y direction, a plurality of lift pins 75 (three in this example) that can be raised and lowered in the Z direction, i.e., the vertical direction, are arranged in parallel at predetermined intervals.

[0030] A clamping mechanism 80 and a lifting mechanism 90 are provided near the periphery of the table 70. The clamping mechanism 80 includes fixing members 80A and 80B that are arranged opposite each other in the X direction (scanning direction) with the support surface 70S of the table 70 sandwiched therebetween. The lifting mechanism 90 includes lifters 90A and 90B that are arranged opposite each other in the Y direction with the support surface 70S of the table 70 sandwiched therebetween.

[0031] The fixing members 80A and 80B are rotatable about shafts 82A and 82B, respectively, and press down the substrate W from above while the substrate W is placed on the table 70. Here, the fixing members 80A and 80B each include three plate-shaped fixing devices.

[0032] The lifters 90A and 90B of the lifting mechanism 90 are movable along the Z direction and can support the transported substrate W while placing the substrate W on the support surface 70S of the table 70. Furthermore, as the ablation processing on the substrate W is completed, the lifters 90A and 90B rise to remove the substrate W from the support surface 70S of the table 70.

[0033] The lifters 90A and 90B are movable along the Y direction as well as the Z direction. As will be described later, the lifters 90A and 90B also function as pressing members that press down the front surface side of the substrate W by moving in the Y and Z directions.

[0034] The lifters 90A and 90B are respectively provided with sensors (hereinafter referred to as warpage detection sensors) 92 and 94 that detect warpage of the substrate W. The warpage detection sensor 92 is configured as an optical sensor here, and includes a light-emitting unit 92A and a light-receiving unit 92B that are arranged opposite each other with the support surface 70S of the table 70 interposed therebetween. The warpage detection sensor 94 also includes a light-emitting unit 94A and a light-receiving unit 94B.

[0035] FIG. 3 is a diagram showing the process of placing and fixing a substrate on a table. FIG. 4 is a diagram showing a flow of the substrate warpage detection process. FIG. 5 is a diagram showing the substrate warpage detection process. The placing and fixing of the substrate W on the table 70 will be explained using FIGS. 5, however, only the warpage detection sensors 92 (92A, 92B) are shown.

[0036] When the substrate W is transported to the laser processing apparatus 100 by the transport mechanism, the lifters 90A and 90B support the transported substrate W together with the lift pins 75 (FIG. 3(A) and S101 in FIG. 4). The lifters 90A and 90B extend in the Y direction and include plates 91A and 91B that form a support surface that supports the substrate W from the bottom side and a pressing surface that presses the substrate W from the top side.

[0037] The lifters 90A and 90B, while supporting the substrate W with the plates 91A and 91B, move down together with the lift pins 75. When the substrate W reaches the support surface 70S of the table 70 and the plates 91A and 91B move away from the bottom surface of the substrate W, the lifters 90A and 90B move in the Y direction toward the retracted positions (FIGS. 3B and 3C, S102 and S103 in FIG. 4).

[0038] The lifters 90A and 90B move to the retracted positions and then rise. As the lifters 90A and 90B start to rise, the warpage detection sensors 92 and 94 are activated and light is projected from the light projecting unit 92A (FIG. 3(D) and S104 in FIG. 4). Here, laser light is irradiated from the light projecting unit 92A.

[0039] As shown in Fig. 5, warpage occurs in the substrate W due to thermal deformation and the like. Here, the height of the edge of the substrate W from the support surface 70S of the table 70 is represented by the symbol "H." Because the warpage detection sensors 92 (92A, 92B), 94 (94A, 94B) are installed below the plates 91A, 91B, for a while after the lifters 90A, 90B start to rise, the light from the light-emitting unit 92A is reflected by the table 70 or the substrate W and does not reach the light-receiving unit 92B (see Figs. 5(A) and (B)).

[0040] As the lifters 90A and 90B continue to rise, the positions of the warpage detection sensors 92 and 94 exceed the warpage height H of the substrate W. At this time, light from the light-projecting units 92A and 94A reaches the light-receiving units 92B and 94B, respectively. The warpage detection sensors 92 and 94 can detect the degree of warpage (height H) of the substrate W in accordance with the light detection by the light-receiving units 92B and 94B (S105 in FIG. 4).

[0041] The control unit 25 stops the lifting of the lifters 90A, 90B based on the detection signals from the warp detection sensors 92, 94. At this time, the lower surfaces of the plates 91A, 91B of the lifters 90A, 90B are positioned above the warp height H of the substrate W. The control unit 25 determines the stop position of the lifters 90A, 90B as the pressing operation start position, and moves them in the Y direction to a predetermined position so as to approach the substrate W.

[0042] The control unit 25 then lowers the lifters 90A and 90B, and the plates 91A and 91B press down on the substrate W from above (FIGS. 3(D) and (E) and S106 and S107 in FIG. 4). In synchronization with the pressing operations of the lifters 90A and 90B, the clamp mechanism 80 presses down on the substrate W, and the substrate W is fixed to the table 70 by vacuum suction.

[0043] The lifters 90A and 90B have no parts that come into contact with the substrate W other than the plates 91A and 91B during the pressing operation, and are not provided with, for example, protrusions that press the side surfaces of the substrate W toward the center of the substrate.

[0044] When the ablation processing on the substrate W is completed, the lifters 90A and 90B move to the retracted positions and descend (FIG. 3(F)). Alternatively, the lifters 90A and 90B may be moved to the retracted positions before the ablation processing. Then, the lifters 90A and 90B, together with the lift pins 75, support the substrate W from the bottom side, from which the suction fixation has been released, and ascend. This causes the substrate W to detach from the table 70.

[0045] As described above, the laser processing apparatus 100 of this embodiment includes the lifting mechanism 90 provided with the lifters 90A, 90B, and the lifters 90A, 90B are provided with the warp detection sensors 92, 94. The warp detection sensors 92, 94 detect warp at the edge of the substrate W when the lifters 90A, 90B place the substrate W on the table 70 and then move up to press down on the upper surface of the substrate W. The lifters 90A, 90B then stop moving up at the warp detection position and perform a pressing operation, i.e., move the lifters 90A, 90B in the horizontal direction (Y direction) and then move down.

[0046] For example, if the substrate W is a glass substrate, it is effective to vacuum-suck the substrate W while pressing it down, but if the substrate W is significantly warped, this will increase the load on the substrate W. In this embodiment, the warp detection sensors 92, 94 detect the warp of the substrate W from the peripheral edge side of the substrate W.

[0047] This makes it possible to properly detect the warpage of the substrate W, and also to properly and reliably perform the pressing operation of pressing the substrate W against the table 70 while reducing the load on the substrate W. The substrate W can be sucked and fixed at a desired position without providing a protrusion or the like that presses the side surface of the substrate W toward the center of the substrate.

[0048] In particular, since the lifting of the lifters 90A and 90B is stopped upon detection of light reception by the warpage detection sensors 92 and 94, it is possible to reliably set the pressing operation according to the warpage height H of the substrate W from the support surface 70S of the table 70. Furthermore, the pressing operation from the upper surface side of the substrate W can be reliably performed while suppressing the descending speed.

[0049] Because the lifters 90A, 90B do not rise to a height higher than necessary, the descent speed during the pressing operation can be suppressed, while preventing a decrease in throughput. In particular, the warp detection sensors 92, 94 are integrally provided below the plates 91A, 91B of the lifters 90A, 90B, and detect warpage of the substrate W while the lifters 90A, 90B rise in conjunction with the lifting of the lifters 90A, 90B. Therefore, a decrease in throughput can be prevented while the lifters 90A, 90B perform both the operation of placing the substrate W on the table 70 and the operation of pressing the substrate W.

[0050] Because the warpage detection sensors 92, 94 detect the degree of warpage (height H) of the substrate W by receiving light, unlike a laser interferometer, it is possible to stop the lifting of the lifters 90A, 90B and start the pressing operation of the lifters 90A, 90B from an appropriate height without actually calculating the amount of warpage (amount of change) as in the case of a laser interferometer. In this way, effective warpage detection can be provided by the inexpensive and compact configuration of the warpage detection sensors 92, 94, and the operation of the lifters 90A, 90B can also be easily controlled by the control unit 25.

[0051] The warpage detection sensors 92, 94 may be configured so that one of the lifters is provided with both a light-emitting unit and a light-receiving unit. The laser light from the light-emitting unit is reflected by the warped substrate W and enters the light-receiving unit until it reaches the warpage height H of the substrate W. Then, when the lifters 90A, 90B rise to a position where the light-emitting unit exceeds the warpage height H of the substrate W, the laser light from the light-emitting unit continues without being reflected by the substrate W, and the light-receiving unit no longer receives the laser light. The control unit 25 detects the position of the lifters 90A, 90B where the light is no longer received as a warpage of the substrate W, and can stop the lifters 90A, 90B from rising and start a pressing operation.

[0052] The warpage detection sensors 92, 94 may be provided separately from the lifters 90A, 90B, rather than being integrated with them, and may be raised and lowered in conjunction with the lifting mechanism 90. For example, the warpage detection sensors 92, 94 may detect the warpage of the substrate W placed on the table 70 from the peripheral edge side of the substrate W while the sensors 92, 94 are raised and lowered relative to the table 70.

[0053] The warpage detection sensors 92, 94 detect warpage of the substrate W while positioned opposite the edge face of the substrate W during the process of lifting and lowering, but warpage may be detected by other methods, or the sensors may be disposed around the periphery of the substrate W or above the surface of the substrate W to detect warpage of the substrate W from an oblique direction or from above. For example, a laser displacement meter may be disposed above the substrate W and scanned to detect warpage of the peripheral edge of the substrate W.

[0054] A pressing member may be provided in addition to the lifters 90A and 90B to perform a pressing operation on the substrate W. Also, a lifting mechanism for placing the substrate W on the table 70 and a lifting mechanism for removing the substrate W from the table 70 may be provided separately.

[0055] The substrate holding device 60 can be incorporated not only into the above-described laser processing device 100, but also into exposure devices such as contact exposure devices and maskless exposure devices that can expose semiconductor wafers, printed wiring boards, LCD glass substrates, etc. Furthermore, it can be incorporated into semiconductor processing devices related to other semiconductor manufacturing processes, such as polishing devices, etching devices, and film formation devices. Alternatively, the substrate holding device 60 can be configured to operate independently of the laser processing device, exposure device, and semiconductor processing device, but to operate in cooperation with them. [Explanation of symbols]

[0056] 10 Light source section 20 Main Unit 25 Control Unit 60 Substrate holding device 70 tables 80 Clamping mechanism 90 Lifting mechanism 90A Lifter 90B Lifter 92 Warp detection sensor 94 Warp detection sensor 100 Laser processing equipment W substrate

Claims

1. A table and a lifting mechanism for placing a substrate on the table; a pressing member that presses the substrate placed on the table from a peripheral edge side of the substrate; a control unit that controls the driving of the pressing member and the lifting mechanism; a warpage detection unit that detects warpage of the substrate placed on the table from a peripheral edge side of the substrate, The substrate holding device, wherein the control unit controls the driving of the pressing member in accordance with the warpage of the substrate.

2. 2. The substrate holding device according to claim 1, wherein the control unit changes a pressing operation start position of the pressing member in accordance with the detected degree of warpage of the substrate.

3. 2. The substrate holding device according to claim 1, wherein the warpage detection unit moves up or down with the substrate placed on the table.

4. the warp detection unit is linked to the lifting mechanism, 2. The substrate holding device according to claim 1, wherein the warpage detection unit detects the warpage of the substrate in accordance with the elevation of the lifting mechanism.

5. the lifting mechanism includes a lifter that is movable along the support surface of the table and also serves as the pressing member; 2. The substrate holding device according to claim 1, wherein the warpage detection unit is provided on the lifter.

6. 2. The substrate holding device according to claim 1, wherein the warpage detection unit comprises a light projecting unit and a light receiving unit that are arranged opposite each other near the periphery of the table.

7. 2. The substrate holding device according to claim 1, wherein the warpage detection unit comprises a light projecting unit and a light receiving unit capable of receiving light projected from the light projecting unit and reflected by the substrate.

8. A table and a lifting mechanism for placing a substrate on the table; a pressing member that presses the substrate placed on the table from a peripheral edge side of the substrate; a control unit that controls the driving of the pressing member and the lifting mechanism; a warpage detection unit that detects warpage of the substrate placed on the table, The substrate holding device is characterized in that the control unit changes a pressing operation start position of the pressing member in accordance with the warp of the substrate detected by the warp detection unit.

9. A laser processing device comprising or operating in cooperation with the substrate holding device according to any one of claims 1 to 8.

10. An exposure apparatus comprising or operating in cooperation with a substrate holding device according to any one of claims 1 to 8.

11. placing the substrate on a table; detecting warpage of the substrate placed on the table from a peripheral edge side of the substrate; performing a pressing operation to press the substrate placed on the table from a peripheral edge side of the substrate; A method of holding a substrate, comprising: A substrate holding method, comprising determining a start position of the pressing operation in accordance with warpage of the substrate.

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