Wafer rotation device, material application device, and wafer rotation method

Abstract

The present invention relates to a wafer rotation device for rotating a wafer while holding an edge part of the wafer in a chuck. This wafer rotation device comprises a temporary placement stand (28) having a wafer placement surface (25) on which a wafer (W) is temporarily placed before being held by a plurality of wafer chucks (5), and a vertical movement actuator (29) that moves the temporary placement stand (28) between a first height and a second height. The wafer placement surface (25) when the temporary placement stand (28) is at a first height is lower or higher than a plurality of edge holding parts (3) of the plurality of wafer chucks (5), and the wafer placement surface (25) when the temporary placement stand (28) is at a second height is at the same height as the plurality of edge holding parts (3).

Description

Wafer Rotation Device, Material Coating Device, and Wafer Rotation Method

[0001] The present invention relates to a wafer rotation device that rotates a wafer while holding an edge portion of the wafer with a chuck.

[0002] The wafer rotation device is used in various processes for wafers. For example, the wafer rotation device is used for applications such as applying a filler to an edge portion of a laminated wafer in which two wafers are bonded together, applying a mask material to an edge portion of a wafer, or polishing an edge portion of a wafer with an abrasive.

[0003] FIG. 35 is a schematic diagram showing an example of a wafer rotation device. The wafer rotation device has a plurality of roller chucks 500 that contact an edge portion of a wafer W. In a state where these roller chucks 500 contact the edge portion of the wafer W, the wafer W is rotated by the rotation of the roller chucks 500. While the wafer W is rotating, the roller chucks 500 themselves rotate, but the positions of the roller chucks 500 are fixed. Therefore, a material such as a filler or a mask material can be applied to the edge portion of the wafer W.

[0004] FIG. 36 is a schematic diagram showing the operation when the wafer W is held by a plurality of roller chucks 500. The wafer W to be processed is conveyed to a predetermined position by a hand 501 of a transfer robot. In a state where the hand 501 of the transfer robot supports the wafer W, the plurality of roller chucks 500 approach the edge portion of the wafer W and contact the edge portion of the wafer W. As a result, the edge portion of the wafer W is held by the plurality of roller chucks 500.

[0005] Japanese Unexamined Patent Application Publication No. 2022 - 36416, Japanese Unexamined Patent Application Publication No. 2023 - 032581

[0006] However, due to its structure, the transport robot's hand 501 cannot always transfer the wafer W to the roller chuck 500 at the same height. In other words, the height of the wafer W when held by multiple roller chucks 500 varies slightly from wafer to wafer. As a result, the position of the edge of the wafer W rotated by the multiple roller chucks 500 changes, and the intended processing of the wafer W's edge may not be achieved.

[0007] Therefore, the present invention provides a technology that enables a wafer chuck to always hold a wafer at the same height.

[0008] In one embodiment, a wafer rotating device is provided for rotating a wafer, comprising: a plurality of wafer chucks each having a plurality of edge holding portions for holding the edges of the wafer; a chuck rotation mechanism that rotates the plurality of wafer chucks to rotate the wafer around a predetermined wafer rotation axis; a temporary stand having a wafer mounting surface on which the wafer is temporarily placed before being held by the plurality of wafer chucks; and a vertical actuator that moves the temporary stand between a first height and a second height, wherein when the temporary stand is at the first height, the wafer mounting surface is lower or higher than the plurality of edge holding portions, and when the temporary stand is at the second height, the wafer mounting surface is at the same height as the plurality of edge holding portions.

[0009] In one embodiment, the temporary storage stand is a plurality of temporary storage stands, each having a wafer mounting surface. In one embodiment, the plurality of wafer chucks and the plurality of temporary storage stands are arranged alternately around the wafer rotation axis. In one embodiment, the temporary storage stand has a positioning projection that protrudes upward from the wafer mounting surface, and the positioning projection has a positioning inclined surface that slopes downward toward the wafer rotation axis. In one embodiment, when the temporary storage stand is at the second height, the wafer mounting surface and the plurality of edge holders are on the same plane.

[0010] In one embodiment, the wafer rotating device further comprises a tilting device for tilting the plurality of wafer chucks and the temporary stand. In one embodiment, the wafer rotating device further comprises a load measuring device for supporting the temporary stand, and a coating amount calculator that acquires a first weight measurement value output from the load measuring device when the wafer is on the temporary stand and before the material is coated on the wafer, acquires a second weight measurement value output from the load measuring device when the wafer is on the temporary stand and after the material has been coated on the wafer, and calculates the amount of the material coated on the wafer by subtracting the first weight measurement value from the second weight measurement value. In one embodiment, a material coating device is provided, comprising the wafer rotating device and a coating module for coating a wafer rotated by the wafer rotating device.

[0011] In one embodiment, a wafer rotation method is provided, which includes placing a wafer on the wafer mounting surface of a temporary storage stand at a first height, moving the temporary storage stand from the first height to a second height using a vertical actuator, holding the edges of the wafer on the wafer mounting surface with a plurality of edge holding parts of a plurality of wafer chucks, and rotating the plurality of wafer chucks with a chuck rotation mechanism to rotate the wafer about a predetermined wafer rotation axis, wherein when the temporary storage stand is at the first height, the wafer mounting surface is lower or higher than the plurality of edge holding parts, and when the temporary storage stand is at the second height, the wafer mounting surface is at the same height as the plurality of edge holding parts.

[0012] In one embodiment, the temporary storage stand is a plurality of temporary storage stands, each having a wafer mounting surface. In one embodiment, the plurality of wafer chucks and the plurality of temporary storage stands are arranged alternately around the wafer rotation axis. In one embodiment, the temporary storage stand has a positioning projection that protrudes upward from the wafer mounting surface, and the positioning projection has a positioning inclined surface that inclins downward toward the wafer rotation axis. In one embodiment, when the temporary storage stand is at the second height, the wafer mounting surface and the plurality of edge holders are on the same plane. In one embodiment, the wafer rotation method further includes holding the edge portion of the wafer with the plurality of edge holders, and then tilting the plurality of wafer chucks and the temporary storage stand from a horizontal position to a vertical position using a tilting device. In one embodiment, the wafer rotation method further includes applying material from a coating module to the wafer while the wafer is rotating. In one embodiment, the wafer rotation method further includes obtaining a first weight measurement value output from a load measuring device supporting the temporary stand when the wafer is on the temporary stand and before the material is applied to the wafer, obtaining a second weight measurement value output from the load measuring device when the wafer is on the temporary stand and after the material has been applied to the wafer, and calculating the amount of the material applied to the wafer by subtracting the first weight measurement value from the second weight measurement value.

[0013] Before being held in the wafer chuck, the wafer is temporarily placed on a temporary support stand. The temporary support stand can maintain a constant wafer height. The wafer chuck can maintain a constant wafer height by holding the wafer's edge on the temporary support stand. As a result, the position of the wafer's edge remains stable when the wafer is rotating, allowing for accurate processing of the wafer's edge.

[0014] This figure shows one embodiment of a wafer rotating device for rotating wafers. This is an enlarged view showing the top of a temporary storage platform. This figure shows an example of a wafer edge being placed on a temporary storage platform. This is a top view showing one embodiment of the arrangement of multiple wafer chucks and multiple temporary storage platforms. This figure shows one embodiment of a wafer rotating device before wafers are placed on multiple temporary storage platforms. This figure shows one embodiment in which the hand of a transport robot places wafers on multiple wafer placement surfaces of multiple temporary storage platforms. This figure shows one embodiment in which multiple temporary storage platforms are raised to a second height where the wafer placement surface is at the same height as the edge holding portion of the wafer chuck. This figure shows one embodiment in which the wafer edge is held by the edge holding portion of the wafer chuck. This figure shows one embodiment in which the temporary storage platform is lowered from the second height to the first height. This figure shows one embodiment in which multiple wafer chucks holding wafers are tilted from a horizontal position to a vertical position. This figure shows one embodiment of a material coating device. This is an enlarged view from the direction indicated by arrow A in Figure 11. This figure shows one embodiment in which multiple wafer chucks holding wafers are tilted from a vertical position to a horizontal position. This figure shows one embodiment in which a temporary storage table is raised from a first height to a second height, and the wafer mounting surface of the temporary storage table is brought into contact with the underside of the wafer. This figure shows one embodiment in which multiple wafer chucks are moved away from the wafer rotation axis. This figure shows one embodiment in which multiple temporary storage tables are moved from a second height to a first height. This figure shows one embodiment in which a wafer is removed from the temporary storage table by the hand of a transport robot. This figure shows another embodiment of the wafer rotating device. This figure shows one embodiment in which multiple temporary storage tables are lowered from a first height to a second height where the wafer mounting surface is at the same height as the edge holding portion of the wafer chuck. This figure shows one embodiment in which the edge portion of the wafer is held by the edge holding portion of the wafer chuck. This figure shows one embodiment in which the temporary storage table is further lowered to a third height lower than the second height. This figure shows yet another embodiment of the wafer rotating device. This figure shows one embodiment in which the hand of a transport robot places wafers onto multiple wafer placement surfaces of multiple temporary placement tables.This figure shows one embodiment in which multiple temporary placement tables are lowered from a first height to a second height where the wafer placement surface is at the same height as the edge holding portion of the wafer chuck. This figure shows one embodiment in which the edge portion of the wafer is sandwiched between the clamp and the edge support surface. This figure shows one embodiment in which the temporary placement tables are further lowered to a third height lower than the second height. This figure shows one embodiment in which the wafer is rotated around the wafer rotation axis. This figure shows one embodiment in which the wafer rotation device of the embodiment described with reference to Figures 22 to 27 is applied to a material coating device. This figure shows yet another embodiment of the wafer rotation device. This figure shows one embodiment of a wafer rotation device equipped with multiple load measuring devices. This figure shows one embodiment in which load measuring devices and coating amount calculators are incorporated into the embodiment described with reference to Figures 18 to 21. This figure shows one embodiment in which load measuring devices and coating amount calculators are incorporated into the embodiment described with reference to Figures 22 to 28. This figure shows one embodiment in which the wafer rotation device of the embodiment described with reference to Figures 1 to 17 is applied to a material coating device. This is a schematic diagram showing the wafer chuck and coating module shown in Figure 33. This is a schematic diagram showing an example of a wafer rotating device. It illustrates the operation when a wafer is held by multiple roller chucks.

[0015] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows one embodiment of a wafer rotating device for rotating a wafer. The wafer rotating device 1 of this embodiment is suitably used as a material coating device for applying a filler material to the edge portion of a laminated wafer formed by bonding two wafers together. However, the wafer rotating device 1 of this embodiment can also be used as a material coating device for applying a mask material to the edge portion of a wafer, a material coating device for applying a coating material to the upper surface of a wafer, and a polishing device for polishing the edge portion of a wafer with a polishing tool (e.g., polishing tape).

[0016] As shown in Figure 1, the wafer rotating device 1 of this embodiment has a plurality of wafer chucks 5, each having a plurality of edge holding parts 3 for holding the edge portion of the wafer W, and a plurality of chuck rotation mechanisms 6 for rotating the plurality of wafer chucks 5. Each wafer chuck 5 of this embodiment is a cylindrical roller chuck. Each edge holding part 3 is an annular groove with a concave cross-sectional shape that engages with the edge portion of the wafer W. Each edge holding part 3 is configured to hold the edge portion of the wafer W by engaging with the edge portion of the wafer W.

[0017] Although Figure 1 shows two wafer chucks 5, the wafer rotating device 1 of this embodiment is equipped with four wafer chucks 5. Therefore, the four edge holding portions 3 of the four wafer chucks 5 hold the edges of the wafer W. The four wafer chucks 5 are arranged around a predetermined wafer rotation axis Cr. This wafer rotation axis Cr is an imaginary rotation centerline. In one embodiment, only three wafer chucks 5 may be provided, or five or more wafer chucks 5 may be provided.

[0018] Multiple wafer chucks 5 are fixed to the upper ends of multiple chuck rotation shafts 8. Each of the multiple chuck rotation shafts 8 is connected to a multiple chuck rotation mechanism 6. Each chuck rotation mechanism 6 comprises an electric motor 10 and a torque transmission mechanism 11 (including, for example, a belt or gears). In other embodiments, the electric motor 10 as a chuck rotation mechanism 6 may be connected to each of the chuck rotation shafts 8. Each chuck rotation shaft 8 extends vertically and is rotatably supported by bearings 14. The bearings 14 and the electric motor 10 are fixed to a motor base 15.

[0019] With multiple wafer chucks 5 holding the edge portion of the wafer W, multiple chuck rotation mechanisms 6 rotate the multiple wafer chucks 5 around their respective axes via multiple chuck rotation shafts 8, causing the wafer W to rotate around the wafer rotation axis Cr.

[0020] The wafer rotating device 1 includes a plurality of chuck moving mechanisms 17 that move a plurality of wafer chucks 5, a plurality of chuck rotation shafts 8, and a plurality of chuck rotation mechanisms 6 in a direction toward the wafer rotation axis Cr and in a direction toward the wafer rotation axis Cr. Each chuck moving mechanism 17 is composed of an actuator such as an air cylinder. The chuck moving mechanism 17 is fixed to a base 20 and connected to a motor base 15 via a connecting member 21. The chuck moving mechanism 17 can move the wafer chucks 5, chuck rotation shafts 8, and chuck rotation mechanisms 6 toward the wafer rotation axis Cr and in a direction toward the wafer rotation axis Cr by moving the motor base 15 horizontally.

[0021] A chuck movement mechanism 17 moves two of the multiple wafer chucks 5, bringing them closer to the wafer rotation axis Cr until the connecting member 21 contacts a stopper 22 fixed to the base 20. When the connecting member 21 is in contact with the stopper 22, the horizontal positions of the two wafer chucks 5 are fixed. These two wafer chucks 5, with their horizontal positions fixed, function as positioning mechanisms for the wafer W. Meanwhile, the remaining wafer chuck 5 of the multiple wafer chucks 5 is moved by another chuck movement mechanism 17 until it contacts the edge of the wafer W. Since the wafer W is held by the two wafer chucks 5 with their horizontal positions fixed, the wafer W can rotate around a predetermined wafer rotation axis Cr.

[0022] The wafer rotating device 1 further comprises a plurality of temporary storage tables 28 having a plurality of wafer mounting surfaces 25 on which wafers W are temporarily placed before being held by the wafer chuck 5, and a vertical actuator 29 for moving the temporary storage tables 28 between a first height and a second height. The first height of the temporary storage tables 28 is such that the plurality of wafer mounting surfaces 25 are lower than the plurality of edge holding parts 3, and the second height of the temporary storage tables 28 is such that the plurality of wafer mounting surfaces 25 are at the same height as the plurality of edge holding parts 3. When the temporary storage tables 28 are at the second height, the plurality of wafer mounting surfaces 25 and the plurality of edge holding parts 3 are on the same plane. The vertical actuator 29 is configured to stationary the plurality of temporary storage tables 28 at the first height and to stationary the plurality of temporary storage tables 28 at the second height.

[0023] Figure 1 shows two temporary support tables 28, but in this embodiment, four temporary support tables 28 are provided. In one embodiment, three temporary support tables 28 may be provided, or five or more temporary support tables 28 may be provided. The multiple temporary support tables 28 are fixed to the support structure 30, and the vertical movement actuators 29 are connected to the support structure 30. The vertical movement actuators 29 are fixed to the base 20. The vertical and horizontal positions of the base 20 are fixed.

[0024] The support structure 30 of this embodiment is a frame structure having an upper frame 31 to which a plurality of temporary placement tables 28 are fixed, a lower frame 32 to which vertical actuators 29 are connected, and a vertical frame 33 connecting the upper frame 31 to the lower frame 32. However, the configuration of the support structure 30 is not limited to the embodiment shown in Figure 1, as long as a plurality of temporary placement tables 28 can be fixed and vertical actuators 29 can be connected.

[0025] In one embodiment, the vertical actuator 29 is composed of an air cylinder. In another embodiment, the vertical actuator 29 may be composed of a combination of a servo motor and a ball screw mechanism. The vertical actuator 29 is fixed to the lower surface of the base 20. In another embodiment, the vertical actuator 29 may be fixed to the upper surface of the base 20. The vertical actuator 29 moves the support structure 30 and the plurality of temporary support tables 28 up and down as a single unit.

[0026] The wafer rotating device 1 can be applied to a material coating device that applies a filler to the edge portion of a wafer W. In one embodiment, the application of the filler to the edge portion of the wafer W is performed while the wafer W rotates in a vertical position. Therefore, the wafer rotating device 1 of this embodiment further includes a plurality of wafer chucks 5, a plurality of chuck rotation mechanisms 6, a plurality of temporary placement tables 28, and a tilting device 38 that tilts the vertical actuator 29.

[0027] The tilting device 38 is connected to the base 20 and is configured to tilt the base 20 from a horizontal position to a vertical position and from a vertical position to a horizontal position. Since the multiple wafer chucks 5, multiple chuck rotation mechanisms 6, multiple chuck movement mechanisms 17, multiple temporary storage tables 28, and vertical actuators 29 are directly or indirectly fixed to the base 20, the multiple wafer chucks 5, multiple chuck rotation mechanisms 6, multiple chuck movement mechanisms 17, multiple temporary storage tables 28, and vertical actuators 29 tilt together with the base 20 from a horizontal position to a vertical position and from a vertical position to a horizontal position. The specific configuration of the tilting device 38 is not particularly limited as long as it has the intended function. For example, the tilting device 38 can be made up of a rotary cylinder or a combination of an electric motor and gears.

[0028] Figure 2 is an enlarged view showing the upper part of the temporary storage stand 28. As shown in Figure 2, each temporary storage stand 28 has a wafer mounting surface 25 on which the edge portion of the wafer W is placed, and a positioning projection 40 that protrudes upward from the wafer mounting surface 25. The positioning projection 40 has a positioning inclined surface 41 that slopes downward toward the wafer rotation axis Cr. In this embodiment, the positioning projection 40 has a frustoconical shape, and the positioning inclined surface 41 also has a frustoconical shape. In other embodiments, the positioning inclined surface 41 may be a slope surface with a shape other than a frustoconical shape.

[0029] The wafer W is temporarily placed on a temporary storage stand 28 before its edges are held by the multiple wafer chucks 5. Figure 3 shows an example of the edges of the wafer W being placed on the temporary storage stand 28. A transport robot (not shown) carries the wafer W into the wafer rotating device 1 until its edges are positioned above the temporary storage stand 28. Once the transport robot places the wafer W on the temporary storage stand 28, the edges of the wafer W slide downward along the positioning inclined surface 41 of the positioning projection 40, as indicated by the arrows, and are received on the wafer mounting surface 25. The edges of the wafer W are placed on the wafer mounting surfaces 25 of the multiple (four in this embodiment) temporary storage stands 28.

[0030] Figure 4 is a top view showing one embodiment of the arrangement of multiple wafer chucks 5 and multiple temporary storage tables 28. As shown in Figure 4, the multiple wafer chucks 5 and multiple temporary storage tables 28 are arranged alternately around the wafer rotation axis Cr. In this embodiment, multiple temporary storage tables 28 are provided, but in other embodiments, a single temporary storage table 28 and a single wafer mounting surface 25 may be provided, as long as the transport robot can place the edge portion of the wafer W horizontally on the wafer mounting surface 25.

[0031] Figure 5 shows one embodiment of the wafer rotating device 1 before the wafer W is placed on the plurality of temporary storage tables 28. As shown in Figure 5, the chuck moving mechanism 17 moves the wafer chuck 5 in a direction away from the wafer rotation axis Cr. The vertical actuator 29 lowers the plurality of temporary storage tables 28 to a first height where the wafer mounting surface 25 is lower than the plurality of edge holding parts 3. The vertical actuator 29 maintains the plurality of temporary storage tables 28 at the first height. When the temporary storage tables 28 are at the first height, the positioning projection 40 and the wafer mounting surface 25 are located below the wafer chuck 5.

[0032] Next, as shown in Figure 6, the hand 45 of the transport robot places the wafer W onto the wafer mounting surfaces 25 of the multiple temporary storage tables 28. As explained with reference to Figure 3, the edge portion of the wafer W is guided by the positioning inclined surface 41 of the positioning projection 40 and placed on the wafer mounting surface 25. After placing the wafer W on the temporary storage tables 28, the hand 45 of the transport robot can quickly move from the wafer rotating device 1 to another location and perform the next operation.

[0033] As shown in Figure 7, the vertical actuator 29 raises the multiple temporary stands 28 from the first height to a second height where the wafer mounting surface 25 is at the same height as the edge holding portion 3 of the wafer chuck 5. The vertical actuator 29 maintains the multiple temporary stands 28 at the second height. As shown in Figure 8, when the multiple temporary stands 28 are at the second height, the chuck movement mechanism 17 moves the wafer chuck 5 toward the wafer rotation axis Cr, and holds the edge portion of the wafer W with the edge holding portion 3 of the wafer chuck 5.

[0034] As explained with reference to Figures 5 to 8, the wafer W is placed on a temporary stand 28 before being held by the wafer chuck 5. The temporary stand 28 can maintain a constant height of the wafer W when it is held by the wafer chuck 5. The wafer chuck 5 can maintain a constant height of the wafer W held by the wafer chuck 5 by holding the edge portion of the wafer W on the temporary stand 28. As a result, the position of the edge portion of the wafer W is stable when the wafer W is rotating, and processing of the edge portion of the wafer W can be performed accurately.

[0035] After the edge portion of the wafer W is held by the edge holding portion 3 of the wafer chuck 5, as shown in Figure 9, the vertical actuator 29 lowers the temporary stand 28 from the second height to the first height. The wafer mounting surface 25 of each temporary stand 28 moves away from the wafer W. Next, as shown in Figure 10, the tilting device 38 tilts the multiple wafer chucks 5, multiple chuck rotation mechanisms 6, multiple chuck movement mechanisms 17, multiple temporary stand 28, and vertical actuator 29 from a horizontal position to a vertical position while the wafer W is held by the multiple wafer chucks 5. Subsequently, the multiple chuck rotation mechanisms 6 rotate the multiple wafer chucks 5, thereby causing the wafer W to rotate around the wafer rotation axis Cr.

[0036] In one embodiment, a filler is applied to the edge of a wafer W while the wafer W is rotating in a vertical position. Figure 11 shows one embodiment of a material application apparatus that applies a filler to the edge of a wafer W while the wafer W, which is in a vertical position, is rotated by a plurality of wafer chucks 5. The material application apparatus comprises a wafer rotating device 1, which has been described with reference to Figures 1 to 10, an application module 50 that applies a filler to the edge of the wafer W rotated by the wafer rotating device 1, and a curing device 51 that cures the filler applied to the edge of the wafer W. Detailed illustration of the wafer rotating device 1 is omitted in Figure 11.

[0037] The wafer W is held in a vertical position by a plurality of wafer chucks 5. As these wafer chucks 5 rotate around their axes, the wafer W rotates around the wafer rotation axis Cr. The coating module 50 is located above the wafer W. The filler material is dispensed from the coating module 50 toward the edge of the wafer W.

[0038] Figure 12 is an enlarged view from the direction indicated by arrow A in Figure 11. As shown in Figure 12, the wafer W applied to this embodiment is a laminated wafer formed by bonding a first wafer W1 and a second wafer W2 together. There is a gap G between the edge portion E1 of the first wafer W1 and the edge portion E2 of the second wafer W2. This gap G is formed around the entire circumference of the wafer W. The coating module 50 is located above the gap G and fills the gap G with filler material by releasing filler material toward the gap G.

[0039] As shown in Figure 11, the curing apparatus 51 is positioned downstream of the coating module 50 in the rotational direction of the wafer W, and is configured to cure the filler applied to the wafer W by the coating module 50. The curing of the filler by the curing apparatus 51 is performed while the wafer W is rotating. In this embodiment, the filler is a thermosetting filler. An example of such a filler is a thermosetting resin.

[0040] The curing device 51 is an air heater and is configured to blow hot air onto the filler material applied to the wafer W. The curing device 51 is configured to allow adjustment of the air pressure and temperature of the blown hot air. The filler material heated by the hot air hardens through a crosslinking reaction. If the filler material contains a solvent, the solvent is evaporated by heating. The curing device 51 is not limited to an air heater; it may also be a lamp heater or other configuration as long as it can heat and harden the filler material.

[0041] In this embodiment, the filler is a thermosetting filler. However, in one embodiment, the filler may be an ultraviolet-curable filler. In this case, the curing device 51 may be a UV irradiation device that irradiates ultraviolet rays to cure the filler. When the filler contains a solvent, a heater such as an air heater may be used in combination to heat and volatilize the solvent. In yet another embodiment, the coating module 50 may be configured to deposit the filler in the gap G by causing a high-speed jet of the filler to collide with the edge portion E1 of the first wafer W1 and the edge portion E2 of the second wafer W2. In this case, the curing device 51 may be omitted in some cases.

[0042] When the application of the filler is completed, the chuck rotation mechanism 6 stops the rotation of the wafer chuck 5, thereby stopping the rotation of the wafer W. As shown in FIG. 13, the tilting device 38 tilts the plurality of wafer chucks 5, the plurality of chuck rotation mechanisms 6, the plurality of chuck movement mechanisms 17, the plurality of temporary placement tables 28, and the vertical movement actuator 29 from a vertical posture to a horizontal posture while the wafer W is held by the plurality of wafer chucks 5.

[0043] As shown in FIG. 14, the vertical movement actuator 29 raises the temporary placement table 28 from the first height to the second height, and brings the wafer placement surface 25 of the temporary placement table 28 into contact with the lower surface of the wafer W. As shown in FIG. 15, the chuck movement mechanism 17 moves the plurality of wafer chucks 5 in a direction away from the wafer rotation axis center Cr. The plurality of wafer chucks 5 move away from the edge portion of the wafer W, and thereby the wafer W is supported by the plurality of wafer placement surfaces 25 of the plurality of temporary placement tables 28.

[0044] As shown in FIG. 16, the vertical movement actuator 29 moves the plurality of temporary placement tables 28 from the second height to the first height. The wafer W is lowered together with these temporary placement tables 28. As shown in FIG. 17, the hand 45 of the transfer robot enters under the wafer W on the temporary placement table 28 and takes out the wafer W from the temporary placement table 28.

[0045] The coating module 50 and curing apparatus 51 shown in Figures 11 and 12 are at the same height as the wafer W held in the wafer chuck 5, i.e., at a second height. If the hand 45 of the transport robot transports the wafer W onto the temporary storage table 28 at the second height, there is a risk that the wafer W will come into contact with the coating module 50 and curing apparatus 51. According to this embodiment, as described with reference to Figures 6 and 17, the operation of placing the wafer W on the temporary storage table 28 and the operation of removing the wafer W from the temporary storage table 28 are performed when the temporary storage table 28 is at a first height lower than the wafer chuck 5. This operation prevents the wafer W on the hand 45 of the transport robot from coming into contact with the coating module 50 and curing apparatus 51.

[0046] Figure 18 shows another embodiment of the wafer rotating device 1. The configuration and operation of this embodiment, which are not specifically described, are the same as those of the embodiment described with reference to Figures 1 to 17, so redundant descriptions are omitted.

[0047] In this embodiment, the first height is higher than the second height. That is, as shown in Figure 18, when the temporary storage table 28 is at the first height, the wafer mounting surface 25 is higher than the multiple edge holding portions 3 of the multiple wafer chucks 5. When the temporary storage table 28 is at the first height, the hand 45 of the transport robot places the wafer W on the multiple wafer mounting surfaces 25 of the multiple temporary storage tables 28. As explained with reference to Figure 3, the edge portion of the wafer W is guided by the positioning inclined surface 41 of the positioning projection 40 and placed on the wafer mounting surface 25. After placing the wafer W on the temporary storage table 28, the hand 45 of the transport robot can quickly move from the wafer rotating device 1 to another location and perform the next operation.

[0048] As shown in FIG. 19, the vertical actuator 29 lowers a plurality of temporary platforms 28 from the first height until the wafer placement surface 25 reaches the second height that is the same as the edge holding portion 3 of the wafer chuck 5. The vertical actuator 29 maintains the plurality of temporary platforms 28 at the second height. As shown in FIG. 20, when the plurality of temporary platforms 28 are at the second height, the chuck moving mechanism 17 moves the wafer chuck 5 in a direction approaching the wafer rotation axis Cr, and the edge holding portion 3 of the wafer chuck 5 holds the edge portion of the wafer W. As shown in FIG. 21, after the edge portion of the wafer W is held by the edge holding portion 3 of the wafer chuck 5, the vertical actuator 29 further lowers the temporary platforms 28 to a third height lower than the second height. The wafer placement surface 25 of each temporary platform 28 moves away from the wafer W.

[0049] The application of the filler using the coating module 50 is executed according to the operations described with reference to FIGS. 10 to 13. The removal of the wafer W from the wafer rotating device 1 can be achieved by performing the operations shown in FIGS. 18 to 21 in reverse.

[0050] FIG. 22 is a diagram showing still another embodiment of the wafer rotating device 1. Since the configuration and operations of this embodiment not particularly described are the same as those of the embodiment described with reference to FIGS. 18 to 21, the overlapping description thereof is omitted. In this embodiment, the wafer W is a single wafer, not a stacked wafer. As shown in FIG. 22, each wafer chuck 5 has an edge support surface 60 that supports the edge portion of the wafer W, a clamp 61 that holds the edge portion of the wafer W on the edge support surface 60, and a clamp actuator 62 that drives the clamp 61. In this embodiment, the edge holding portion 3 of each wafer chuck 5 is constituted by the clamp 6I and the edge support surface 60.

[0051] Multiple (four in this embodiment) wafer chucks 5 are fixed to the upper ends of multiple chuck rotation shafts 8. The multiple chuck rotation shafts 8 are connected to a chuck rotation mechanism 6. The chuck rotation mechanism 6 includes an electric motor 10 and a torque transmission mechanism 11 (including a belt 63 and pulleys 64). The lower ends of the multiple chuck rotation shafts 8 are fixed to the pulleys 64. The belt 63 connects the electric motor 10 and the pulleys 64. Each chuck rotation shaft 8 extends vertically and rotates together with the pulleys 64 about the wafer rotation axis Cr.

[0052] Figure 23 shows one embodiment when the temporary storage stand 28 is at a first height. When the temporary storage stand 28 is at the first height, the wafer mounting surface 25 is higher than the multiple edge holding portions 3 of the multiple wafer chucks 5. As shown in Figure 23, when the temporary storage stand 28 is at the first height, the hand 45 of the transport robot places the wafer W on the multiple wafer mounting surfaces 25 of the multiple temporary storage stands 28. As described with reference to Figure 3, the edge portion of the wafer W is guided by the positioning inclined surface 41 of the positioning projection 40 and placed on the wafer mounting surface 25. After placing the wafer W on the temporary storage stand 28, the hand 45 of the transport robot can quickly move from the wafer rotating device 1 to another location and perform the next operation.

[0053] As shown in Figure 24, with the clamp 61 open, the vertical actuator 29 lowers the multiple temporary stands 28 from the first height to a second height where the wafer mounting surface 25 is at the same height as the edge holding portion 3 (including the clamp 61 and edge support surface 60) of the wafer chuck 5. The vertical actuator 29 maintains the multiple temporary stands 28 at the second height. The edges of the wafers W are placed on the edge support surfaces 60 of the multiple wafer chucks 5. As shown in Figure 25, the clamp actuator 62 closes the clamp 61, thereby clamping the edges of the wafers W between the clamp 61 and the edge support surface 60. As shown in Figure 26, the vertical actuator 29 further lowers the temporary stands 28 to a third height, which is lower than the second height. The wafer mounting surface 25 of each temporary stand 28 is separated from the wafers W. As shown in Figure 27, the chuck rotation mechanism 6 rotates the multiple wafer chucks 5, thereby causing the wafer W to rotate around the wafer rotation axis Cr. In this embodiment, the multiple wafer chucks 5 rotate together with the wafer W around the wafer rotation axis Cr.

[0054] The removal of the wafer W from the wafer rotating device 1 can be achieved by reversing the operations shown in Figures 23 to 27.

[0055] Figure 28 shows one embodiment in which the wafer rotating device 1 of the embodiment described with reference to Figures 22 to 27 is applied to a material coating device. The material coating device of this embodiment comprises the wafer rotating device 1 of the embodiment described with reference to Figures 22 to 27 and a coating module 70 that applies a material (e.g., coating material) to the upper surface of a wafer W rotated by the wafer rotating device 1. The coating module 70 is positioned above the wafer W held in the wafer chuck 5 and is located on the wafer rotation axis Cr. In this embodiment, the wafer W is rotated in a horizontal position, and the material (e.g., coating material) is applied from the coating module 70 to the upper surface of the rotating wafer W.

[0056] Figure 29 shows yet another embodiment of the wafer rotating device 1. The configuration and operation of this embodiment, which are not specifically described, are the same as those of the embodiment described with reference to Figures 1 to 17, so a redundant explanation is omitted.

[0057] As shown in Figure 29, the wafer rotating device 1 further includes a load measuring device 75 that supports a plurality of temporary placement tables 28, and a coating amount calculator 76 electrically connected to the load measuring device 75. The load measuring device 75 is incorporated into a support structure 30 that supports the plurality of temporary placement tables 28. More specifically, the load measuring device 75 is positioned between a first upper frame 31A and a second upper frame 31B of the support structure 30. The plurality of temporary placement tables 28 are fixed to the first upper frame 31A. The load measuring device 75 is configured to measure the weight of the wafers W on the plurality of temporary placement tables 28. In this embodiment, the load measuring device 75 measures the weight of the wafers W on the plurality of temporary placement tables 28. The measured weight is output from the load measuring device 75 and sent to the coating amount calculator 76. An example of the load measuring device 75 is a load cell.

[0058] The coating amount calculator 76 is configured to calculate the amount of material applied to the wafer W from a first weight measurement output from the load measuring device 75 before the material is applied to the wafer W, and a second weight measurement output from the load measuring device 75 after the material is applied to the wafer W. As explained with reference to Figures 11 and 12, the filler is applied from the coating module 50 to the edge portion of the wafer W, which is rotated by the wafer rotating device 1. Therefore, the second weight measurement output from the load measuring device 75 after the filler is applied is greater than the first weight measurement output from the load measuring device 75 before the coating is applied. The coating amount calculator 76 can calculate the amount of filler applied to the wafer W by subtracting the first weight measurement from the second weight measurement.

[0059] The first and second weight measurements are weight measurements output from the load measuring device 75 when the multiple wafer chucks 5 are separated from the wafer W and the wafer W is horizontally supported on the multiple temporary support tables 28, as shown in Figure 29. The application of the filler to the edges of the wafer W is performed after the first weight measurement is obtained and before the second weight measurement is obtained. In one embodiment, if the amount of filler calculated by the application amount calculator 76 is less than a threshold, the application of the filler to the edges of the wafer W is performed again.

[0060] The coating amount calculator 76 consists of at least one computer. The coating amount calculator 76 includes a storage device 76a in which a program is stored, and an arithmetic unit 76b that performs calculations according to the instructions contained in the program. The storage device 76a includes a main memory such as random access memory (RAM) and an auxiliary storage device such as a hard disk drive (HDD) or solid state drive (SSD). Examples of the arithmetic unit 76b include a CPU (central processing unit) and a GPU (graphics processing unit). However, the specific configuration of the coating amount calculator 76 is not limited to these examples.

[0061] The arrangement of the load measuring devices 75 is not limited to the embodiment shown in Figure 29, as long as the load measuring devices 75 can measure the weight of the wafers W on the temporary placement tables 28. Figure 30 shows one embodiment of a wafer rotating device 1 equipped with a plurality of load measuring devices 75. In the embodiment shown in Figure 30, the plurality of load measuring devices 75 are each connected to a plurality of temporary placement tables 28 and support these plurality of temporary placement tables 28. The plurality of load measuring devices 75 are electrically connected to a coating amount calculator 76. In this embodiment, the load measuring devices 75 measure the weight of the wafers W on the plurality of temporary placement tables 28.

[0062] The embodiments of the load measuring device 75 and the coating amount calculator 76 described with reference to Figures 29 and 30 can be incorporated into the embodiments described with reference to Figures 18 to 28. For example, Figure 31 shows one embodiment in which the load measuring device 75 and the coating amount calculator 76 are incorporated into the embodiments described with reference to Figures 18 to 21, and Figure 32 shows one embodiment in which the load measuring device 75 and the coating amount calculator 76 are incorporated into the embodiments described with reference to Figures 22 to 28.

[0063] Figure 33 shows one embodiment in which the wafer rotating device 1 of the embodiment described with reference to Figures 1 to 17 is applied to a material coating device. The material coating device of this embodiment comprises the wafer rotating device 1 of the embodiment described with reference to Figures 1 to 17 and a coating module 80 that applies material (e.g., mask material) to the edge portion of the wafer W rotated by the wafer rotating device 1. The coating module 80 is positioned radially outward of the wafer W held by the wafer chuck 5.

[0064] Figure 34 is a schematic diagram showing the wafer chuck 5 and coating module 80 shown in Figure 33. As shown in Figure 34, the wafer W is rotated by the wafer chuck 5 around the wafer rotation axis Cr in a horizontal position, and material (e.g., mask material) is applied to the edge of the rotating wafer W from the coating module 80. In this embodiment, the tilting device 38 may not be provided.

[0065] The coating module 80 described with reference to Figures 33 and 34 may be combined with the wafer rotating device 1 of the embodiment described with reference to Figures 18 to 21. Furthermore, the load measuring device 75 and coating amount calculator 76 described above may be incorporated into the material coating device described with reference to Figures 33 and 34.

[0066] The embodiments described above are intended to enable persons with ordinary skill in the art to implement the present invention. Various modifications of the above embodiments can be made naturally by those skilled in the art, and the technical idea of ​​the present invention can be applied to other embodiments as well. Therefore, the present invention is not limited to the embodiments described, but is to be interpreted in the broadest sense according to the technical idea defined by the claims.

[0067] The present invention can be used in a wafer rotating device that rotates a wafer while holding its edge with a chuck.

[0068] W Wafer Cr Wafer rotation axis 1 Wafer rotation device 3 Edge holding part 5 Wafer chuck 6 Chuck rotation mechanism 8 Chuck rotation shaft 10 Electric motor 11 Torque transmission mechanism 14 Bearing 15 Motor base 17 Chuck movement mechanism 20 Base 21 Connecting member 22 Stopper 25 Wafer mounting surface 28 Temporary stand 29 Vertical actuator 30 Support structure 31 Upper frame 32 Lower frame 33 Vertical frame 38 Tilting device 40 Positioning projection 41 Positioning inclined surface 45 Hand 50 Coating module 51 Curing device 60 Edge support surface 61 Clamp 62 Clamp actuator 63 Belt 64 Pulley 75 Load measuring device 76 Coating amount calculator 80 Coating module

Claims

1. A wafer rotating device for rotating a wafer, comprising: a plurality of wafer chucks each having a plurality of edge holding portions for holding the edges of the wafer; a chuck rotation mechanism for rotating the plurality of wafer chucks to rotate the wafer around a predetermined wafer rotation axis; a temporary stand having a wafer mounting surface on which the wafer is temporarily placed before being held by the plurality of wafer chucks; and a vertical actuator for moving the temporary stand between a first height and a second height, wherein when the temporary stand is at the first height, the wafer mounting surface is lower or higher than the plurality of edge holding portions, and when the temporary stand is at the second height, the wafer mounting surface is at the same height as the plurality of edge holding portions.

2. The wafer rotating device according to claim 1, wherein the temporary placement stand is a plurality of temporary placement stands, each having a wafer placement surface.

3. The wafer rotating apparatus according to claim 2, wherein the plurality of wafer chucks and the plurality of temporary placement tables are arranged alternately around the wafer rotation axis.

4. The wafer rotating device according to claim 1, wherein the temporary placement stand has a positioning projection that protrudes upward from the wafer placement surface, and the positioning projection has a positioning inclined surface that inclins downward toward the wafer rotation axis.

5. The wafer rotating device according to claim 1, wherein when the temporary support stand is at the second height, the wafer mounting surface and the plurality of edge holders are on the same plane.

6. The wafer rotating device according to claim 1, further comprising a tilting device for tilting the plurality of wafer chucks and the temporary placement table.

7. The wafer rotating device according to claim 1, further comprising a load measuring device that supports the temporary stand, and a coating amount calculator that acquires a first weight measurement value output from the load measuring device when the wafer is on the temporary stand and before the material is coated on the wafer, acquires a second weight measurement value output from the load measuring device when the wafer is on the temporary stand and after the material has been coated on the wafer, and calculates the amount of the material coated on the wafer by subtracting the first weight measurement value from the second weight measurement value.

8. A material coating apparatus comprising a wafer rotating apparatus according to any one of claims 1 to 7, and a coating module for coating a material onto a wafer rotated by the wafer rotating apparatus.

9. A wafer rotation method comprising: placing a wafer on the wafer mounting surface of a temporary storage stand at a first height; moving the temporary storage stand from the first height to a second height using a vertical actuator; holding the edge portion of the wafer on the wafer mounting surface with a plurality of edge holding portions of a plurality of wafer chucks; and rotating the plurality of wafer chucks with a chuck rotation mechanism to rotate the wafer about a predetermined wafer rotation axis, wherein the wafer mounting surface is lower or higher than the plurality of edge holding portions when the temporary storage stand is at the first height, and the wafer mounting surface is at the same height as the plurality of edge holding portions when the temporary storage stand is at the second height.

10. The wafer rotation method according to claim 9, wherein the temporary placement stand is a plurality of temporary placement stands, each having a wafer placement surface.

11. The wafer rotation method according to claim 10, wherein the plurality of wafer chucks and the plurality of temporary placement stands are arranged alternately around the wafer rotation axis.

12. The wafer rotation method according to claim 9, wherein the temporary placement stand has a positioning projection that protrudes upward from the wafer placement surface, and the positioning projection has a positioning inclined surface that is inclined downward toward the wafer rotation axis.

13. The wafer rotation method according to claim 9, wherein when the temporary support stand is at the second height, the wafer mounting surface and the plurality of edge holders are on the same plane.

14. The wafer rotation method according to claim 9, further comprising holding the edge portion of the wafer with the plurality of edge holding portions, and then tilting the plurality of wafer chucks and the temporary stand from a horizontal position to a vertical position using a tilting device.

15. The wafer rotation method according to claim 9, further comprising applying a material from a coating module to the wafer while the wafer is rotating.

16. The wafer rotation method according to claim 15, further comprising: obtaining a first weight measurement value output from a load measuring device supporting the temporary stand when the wafer is on the temporary stand and before the material is applied to the wafer; obtaining a second weight measurement value output from the load measuring device when the wafer is on the temporary stand and after the material has been applied to the wafer; and calculating the amount of the material applied to the wafer by subtracting the first weight measurement value from the second weight measurement value.

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