Material coating apparatus and material coating method

Abstract

The present invention provides a material coating apparatus that can accurately determine the amount of filler applied to the gap between the edge of the first wafer and the edge of the second wafer. [Solution] The material coating apparatus 1 includes a coating module 3 for coating the edges of a stacked wafer Ws, a load measuring device 21 for measuring the weight of the stacked wafer Ws, and a coating amount calculator 22 that acquires a first weight measurement value output from the load measuring device 21 before the filler material F is coated on the stacked wafer Ws, acquires a second weight measurement value output from the load measuring device 21 when the filler material F is coated on the stacked wafer Ws or after the filler material F has been coated on the stacked wafer Ws, and calculates the amount of filler material F coated on the stacked wafer Ws by subtracting the first weight measurement value from the second weight measurement value.

Description

Technical Field

[0001] The present invention relates to a material coating apparatus and a material coating method for applying a filler to an edge portion of a stacked wafer composed of a plurality of wafers bonded to each other, and particularly relates to a technique for measuring the amount of the filler applied to the edge portion of the stacked wafer.

Background Art

[0002] In recent years, in order to achieve further high density and high functionality of semiconductor devices, the development of a three-dimensional mounting technique for three-dimensionally integrating a plurality of wafers has been progressing. In the three-dimensional mounting technique, for example, the device surface of a first wafer on which an integrated circuit and electrical wiring are formed is joined to the device surface of a second wafer on which an integrated circuit and electrical wiring are formed. Further, after the first wafer is joined to the second wafer, the second wafer is thinned by a polishing apparatus or a grinding apparatus. In this way, integrated circuits can be stacked in a direction perpendicular to the device surfaces of the first wafer and the second wafer.

[0003] In the three-dimensional mounting technique, three or more wafers may be joined. For example, after the second wafer joined to the first wafer is thinned, the third wafer is joined to the second wafer, and the third wafer is thinned. In this specification, the form of a plurality of wafers joined to each other may be referred to as a "stacked wafer".

[0004] Normally, the edge portion of a wafer is polished in advance into a rounded shape or a chamfered shape in order to prevent cracking or chipping. When the second wafer having such a shape is ground, as a result, a sharp end portion is formed on the second wafer. This sharp end portion (hereinafter referred to as a knife edge portion) is formed by the back surface of the ground second wafer and the outer peripheral surface of the second wafer. Such a knife edge portion is liable to chip due to physical contact, and the stacked wafer itself may be damaged during the conveyance of the stacked wafer. Further, if the joining between the first wafer and the second wafer is not sufficient, the second wafer may crack during grinding.

[0005] Therefore, to prevent cracking and chipping at the knife edge, a filler material is applied to the edge of the stacked wafers before grinding the second wafer. The filler material is applied to the gap between the edge of the first wafer and the edge of the second wafer. The filler material supports the knife edge formed after grinding the second wafer, preventing cracking and chipping of the knife edge. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-032581 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The process of applying filler material to the edges of the laminated wafer ends when a predetermined application time has elapsed. Therefore, the amount of filler material applied is estimated from the application time. However, the application time may not accurately reflect the actual amount applied, and filling defects such as insufficient or excessive filler material application may occur. If the laminated wafer is processed in subsequent processes with filling defects, it may damage the laminated wafer or adversely affect the performance of the laminated wafer and the process.

[0008] Therefore, the present invention provides a material coating apparatus and a material coating method that can accurately determine the amount of filler applied to the gap between the edge of the first wafer and the edge of the second wafer. [Means for solving the problem]

[0009] In one embodiment, a material coating apparatus is provided for coating the edge portion of a stacked wafer, comprising: a wafer holding unit for holding the stacked wafer; a rotation mechanism for rotating the wafer holding unit to rotate the stacked wafer around a predetermined wafer rotation axis; a coating module for coating the edge portion of the stacked wafer on the wafer holding unit rotated by the rotation mechanism; a load measuring device for measuring the weight of the stacked wafer; and a coating amount calculator that acquires a first weight measurement value output from the load measuring device before the filler is coated on the stacked wafer, acquires a second weight measurement value output from the load measuring device when the filler is coated on the stacked wafer or after the filler is coated on the stacked wafer, and calculates the amount of the filler coated on the stacked wafer by subtracting the first weight measurement value from the second weight measurement value.

[0010] In one embodiment, the load measuring device supports the wafer holding portion. In one embodiment, the wafer holding unit comprises a plurality of roller chucks, and the load measuring device comprises a plurality of load measuring devices that each support the plurality of roller chucks. In one embodiment, the wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks for holding the stacked wafers in a vertical position, and the load measuring device is a plurality of load measuring devices attached to each of the plurality of lower roller chucks. In one embodiment, the wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks for holding the stacked wafers in a vertical position, and the load measuring device is positioned between the plurality of lower roller chucks. In one embodiment, the coating amount calculator is configured to obtain the second weight measurement value output from the load measuring device when the filler is being coated onto the laminated wafer, calculate the amount of the filler applied to the laminated wafer by subtracting the first weight measurement value from the second weight measurement value, and determine the coating endpoint when the amount of the filler reaches a predetermined filling threshold.

[0011] In one embodiment, a material coating method is provided for coating the edge portion of a stacked wafer, wherein the stacked wafer is held by a wafer holder, the wafer holder is rotated by a rotation mechanism to rotate the stacked wafer around a predetermined wafer rotation axis, a coating module is applied to the edge portion of the rotating stacked wafer, a first weight measurement value is obtained from a load measuring device that measures the weight of the stacked wafer before the filler is applied to the stacked wafer, a second weight measurement value is obtained from the load measuring device when the filler is applied to the stacked wafer or after the filler is applied to the stacked wafer, and the amount of the filler applied to the stacked wafer is calculated by subtracting the first weight measurement value from the second weight measurement value.

[0012] In one embodiment, the load measuring device supports the wafer holding portion. In one embodiment, the wafer holding unit comprises a plurality of roller chucks, and the load measuring device comprises a plurality of load measuring devices that each support the plurality of roller chucks. In one embodiment, the wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks for holding the stacked wafers in a vertical position, and the load measuring device is a plurality of load measuring devices attached to each of the plurality of lower roller chucks. In one embodiment, the wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks for holding the stacked wafers in a vertical position, and the load measuring device is positioned between the plurality of lower roller chucks. In one embodiment, the second weight measurement is a measurement output from the load measuring instrument when the filler is being applied to the laminated wafer, and the material application method further includes determining an application endpoint where the amount of the filler reaches a predetermined filling threshold. [Effects of the Invention]

[0013] The difference between the first weight measurement value obtained before the filler is applied to the stacked wafer and the second weight measurement value obtained when the filler is being applied to the stacked wafer or after the filler has been applied to the stacked wafer corresponds to the amount of the filler applied to the peripheral portion of the stacked wafer. Therefore, the coating amount calculator can accurately determine the amount of the filler applied to the stacked wafer by subtracting the first weight measurement value from the second weight measurement value.

Brief Description of the Drawings

[0014] [Figure 1] It is a side view showing an embodiment of the material coating device. [Figure 2] It is a plan view showing an embodiment of the material coating device. [Figure 3] It is a flowchart showing an embodiment of applying a filler to a stacked wafer. [Figure 4] It is a flowchart showing another embodiment of applying a filler to a stacked wafer. [Figure 5] It is a front view showing another embodiment of the material coating device. [Figure 6] It is an enlarged view seen from the direction indicated by arrow A in FIG. 5. [Figure 7] It is a front view showing still another embodiment of the material coating device. [Figure 8] It is a view showing a state where the weight of the stacked wafer is being measured by a load measuring device. [Figure 9] It is a flowchart showing an embodiment of applying a filler to a stacked wafer.

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing an embodiment of the material application device 1, and FIG. 2 is a plan view showing an embodiment of the material application device 1. The material application device 1 is a device for applying a filler F to a laminated wafer Ws in which a first wafer W1 and a second wafer W2 are bonded. The material application device 1 includes a wafer holding unit 2 that horizontally holds and rotates the laminated wafer Ws, an application module 3 that applies the filler F to the laminated wafer Ws, a curing device 4 for curing the applied filler F, and an operation control unit 10 that controls the operations of the wafer holding unit 2, the application module 3, and the curing device 4.

[0016] The operation control unit 10 is composed of at least one computer. The operation control unit 10 includes a storage device 10a in which a program is stored and an arithmetic device 10b that executes arithmetic operations according to instructions included in the program. The storage device 10a includes a main storage device such as a random access memory (RAM) and an auxiliary storage device such as a hard disk drive (HDD) and a solid state drive (SSD). Examples of the arithmetic device 10b include a CPU (central processing unit) and a GPU (graphics processing unit). However, the specific configuration of the operation control unit 10 is not limited to these examples.

[0017] The wafer holding unit 2 includes a wafer stage 12 that holds the back surface (lower surface) of the laminated wafer Ws by vacuum suction and a rotating shaft 15 connected to the central portion of the wafer stage 12. The laminated wafer Ws is placed on the wafer stage 12 such that the center of the laminated wafer Ws coincides with the axis of the rotating shaft 15. The material application device 1 includes a rotation mechanism 18 that rotates the wafer stage 12 and the rotating shaft 15 of the wafer holding unit 2. The rotation mechanism 18 includes a motor (not shown). As shown in FIG. 1, the rotation mechanism 18 is configured to integrally rotate the wafer stage 12 and the laminated wafer Ws about the wafer rotation axis center Cr in the direction indicated by the arrow. In the present embodiment, the wafer rotation axis center Cr extends in the vertical direction.

[0018] The coating module 3 is located radially outward of the stacked wafer Ws on the wafer holding section 2, and is configured to coat the filler material F into the gap G between the edge portion E1 of the first wafer W1 and the edge portion E2 of the second wafer W2 of the stacked wafer Ws. This gap G is formed around the entire circumference of the stacked wafer Ws. The coating module 3 is positioned to face the gap G between the edge portion E1 of the first wafer W1 and the edge portion E2 of the second wafer W2.

[0019] The specific configuration of the coating module 3 is not particularly limited, as long as the coating module 3 can discharge the filler F toward the gap G between the stacked wafers Ws. In one embodiment, the coating module 3 may consist of a combination of a piston and a syringe configured to discharge the filler F by gas pressure, or it may consist of a screw feeder.

[0020] As shown in Figures 1 and 2, the curing apparatus 4 is located radially outward of the stacked wafer Ws on the wafer holding section 2. The curing apparatus 4 is positioned downstream of the coating module 3 in the rotational direction of the stacked wafer Ws and is configured to cure the filler F applied to the stacked wafer Ws by the coating module 3. The curing of the filler F by the curing apparatus 4 is performed while the stacked wafer Ws is rotated. In this embodiment, the filler F is a thermosetting filler F. An example of such a filler F is a thermosetting resin.

[0021] The curing apparatus 4 is an air heater configured to blow hot air onto the filler material F applied to the laminated wafer Ws. The curing apparatus 4 is configured to allow adjustment of the air pressure and temperature of the blown hot air. The filler material F heated by the hot air hardens through a crosslinking reaction. If the filler material F contains a solvent, the solvent is evaporated by heating. The curing apparatus 4 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 F.

[0022] In this embodiment, the filler F is a thermosetting filler, but in one embodiment, the filler F may be an ultraviolet-curable filler. In this case, the curing device 4 may be a UV irradiation device that cures the filler F by irradiating it with ultraviolet light. If the filler F contains a solvent, it may be heated using an air heater or the like to volatilize the solvent. In yet another embodiment, the coating module 3 may be configured to deposit the filler F in the gap G by causing a high-speed jet of the filler F 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 4 may be omitted.

[0023] The material coating apparatus 1 further includes a load measuring device 21 for measuring the weight of a stacked wafer Ws, and a coating amount calculator 22 for calculating the amount of filler F coated on the stacked wafer Ws from the measured weight. The load measuring device 21 is incorporated into the wafer holding unit 2. More specifically, the load measuring device 21 is supported by a rotating shaft 15, and the load measuring device 21 supports the wafer stage 12. The load measuring device 21 is positioned between the wafer stage 12 and the rotating shaft 15. Therefore, the load measuring device 21 can measure the weight of the stacked wafer Ws on the wafer stage 12.

[0024] The coating amount calculator 22 is electrically connected to the operation control unit 10. The coating amount calculator 22 is configured to acquire a first weight measurement value output from the load measuring device 21 before the filler material F is applied to the laminated wafer Ws, acquire a second weight measurement value output from the load measuring device 21 when the filler material F is applied to the laminated wafer Ws, or after the filler material F has been applied to the laminated wafer Ws, and calculate the amount of filler material F applied to the laminated wafer Ws by subtracting the first weight measurement value from the second weight measurement value. The difference between the first weight measurement value and the second weight measurement value corresponds to the amount of filler material F applied to the periphery of the laminated wafer Ws. Therefore, the coating amount calculator 22 can accurately determine the amount of filler material F applied to the laminated wafer Ws by subtracting the first weight measurement value from the second weight measurement value.

[0025] The coating amount calculator 22 consists of at least one computer. The coating amount calculator 22 includes a storage device 22a in which a program is stored, and an arithmetic unit 22b that performs calculations according to the instructions contained in the program. The storage device 22a 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 22b include a CPU (central processing unit) and a GPU (graphics processing unit). However, the specific configuration of the coating amount calculator 22 is not limited to these examples. In one embodiment, the coating amount calculator 22 and the operation control unit 10 may consist of a single computer.

[0026] Figure 3 is a flowchart showing one embodiment of applying a filler material F to a stacked wafer Ws. In step 101, the stacked wafer Ws is transported to the wafer holding unit 2 by a transport robot (not shown) and placed on the wafer stage 12. The stacked wafer Ws is held by the wafer stage 12 of the wafer holding unit 2. In step 102, the load measuring device 21 outputs a first weight measurement value while the stacked wafer Ws is held in the wafer holding unit 2. The coating amount calculator 22 obtains the first weight measurement value from the load measuring device 21. In step 103, the operation control unit 10 gives a command to the rotation mechanism 18 to rotate the wafer holding unit 2 and the stacked wafer Ws by the rotation mechanism 18, and at the same time gives a command to the coating module 3 to coat the filler material F onto the edge portion of the stacked wafer Ws.

[0027] In step 104, the operation control unit 10 issues a command to the coating module 3 when a predetermined time has elapsed to finish coating the edges of the stacked wafer Ws with the filler F. Furthermore, the operation control unit 10 issues a command to the rotation mechanism 18 to stop the rotation of the stacked wafer Ws. In step 105, the load measuring device 21 outputs a second weight measurement value while the stacked wafer Ws is held in the wafer holding unit 2. The coating amount calculator 22 obtains the second weight measurement value from the load measuring device 21. In step 106, the coating amount calculator 22 calculates (determines) the amount of filler F coated on the laminated wafer Ws by subtracting the first weight measurement from the second weight measurement.

[0028] Figure 4 is a flowchart showing another embodiment in which filler material F is applied to a stacked wafer Ws. In step 201, the stacked wafer Ws is transported to the wafer holding unit 2 by a transport robot (not shown) and placed on the wafer stage 12. The stacked wafer Ws is held by the wafer stage 12 of the wafer holding unit 2. In step 202, the load measuring device 21 outputs a first weight measurement value while the stacked wafer Ws is held in the wafer holding unit 2. The coating amount calculator 22 obtains the first weight measurement value from the load measuring device 21.

[0029] In step 203, the operation control unit 10 commands the rotation mechanism 18 to rotate the wafer holding unit 2 and the stacked wafer Ws using the rotation mechanism 18, and simultaneously commands the coating module 3 to coat the edges of the stacked wafer Ws with the filler material F.

[0030] In step 204, the load measuring device 21 outputs a second weight measurement when the filler F is applied to the edge of the stacked wafer Ws. The coating amount calculator 22 obtains the second weight measurement from the load measuring device 21.

[0031] In step 205, the coating amount calculator 22 calculates (determines) the amount of filler F coated on the laminated wafer Ws by subtracting the first weight measurement from the second weight measurement. In step 206, the coating amount calculator 22 determines whether the amount of filler F has reached a predetermined filling threshold. If the amount of filler F has not reached the predetermined filling threshold (NO in step 206), the process flow returns to step 204.

[0032] In step 207, if the amount of filler F reaches a predetermined filling threshold (YES in step 206), the coating amount calculator 22 determines the coating endpoint where the amount of filler F has reached the filling threshold. The coating amount calculator 22 transmits a detection signal indicating the coating endpoint to the operation control unit 10. In step 208, when the operation control unit 10 receives a detection signal indicating the coating endpoint, it issues a command to the coating module 3 to terminate the coating of the filler F to the edges of the stacked wafer Ws. Furthermore, the operation control unit 10 issues a command to the rotation mechanism 18 to stop the rotation of the wafer stage 12 of the wafer holding unit 2 and the stacked wafer Ws.

[0033] Figure 5 is a front view showing another embodiment of the material coating apparatus 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 4, so redundant descriptions are omitted.

[0034] The material coating apparatus 1 of this embodiment includes a wafer holding section 2 equipped with a plurality of wafer chucks 25A, 25B that hold the edges of stacked wafers Ws in a vertical position, and a plurality of rotation mechanisms 18 that rotate the plurality of wafer chucks 25A, 25B. The wafer chucks 25A, 25B of this embodiment are cylindrical roller chucks. The stacked wafers Ws are held in a vertical position by the plurality of wafer chucks 25A, 25B.

[0035] The wafer chucks 25A and 25B include a plurality of upper wafer chucks 25A that hold the upper part of the edge portion of the stacked wafer Ws, and a plurality of lower wafer chucks 25B that hold the lower part of the edge portion of the stacked wafer Ws. The plurality of upper wafer chucks 25A are located above a predetermined wafer rotation axis Cr, and the plurality of lower wafer chucks 25B are located below the wafer rotation axis Cr. In this embodiment, the wafer rotation axis Cr extends horizontally. Each of the wafer chucks 25A and 25B has an annular groove (not shown). The stacked wafer Ws is held in the wafer chucks 25A and 25B by the engagement of the edge portion of the stacked wafer Ws with the annular groove of the wafer chucks 25A and 25B.

[0036] Each of the multiple lower wafer chucks 25B incorporates multiple load measuring devices 21 that contact the edge portion of the stacked wafer Ws. Each load measuring device 21 constitutes a part of the annular groove of each lower wafer chuck 25B. Each load measuring device 21 rotates integrally with the lower wafer chuck 25B while supporting the edge portion of the stacked wafer Ws. The multiple load measuring devices 21 are electrically connected to the coating amount calculator 22. Each load measuring device 21 measures the weight of the stacked wafer Ws, and the measured weight is transmitted from each load measuring device 21 to the coating amount calculator 22.

[0037] The coating amount calculator 22 is configured to acquire a first weight measurement value output from the load measuring device 21 before the filler material is applied to the stacked wafer Ws, acquire a second weight measurement value output from the load measuring device 21 when the filler material is applied to the stacked wafer Ws, or after the filler material has been applied to the stacked wafer Ws, and calculate the amount of filler material applied to the stacked wafer Ws by subtracting the first weight measurement value from the second weight measurement value.

[0038] In this embodiment, multiple load measuring devices 21 are provided. Therefore, the first weight measurement may be the sum or average value of multiple weight measurements output from the multiple load measuring devices 21 before the filler material is applied to the laminated wafer Ws. The second weight measurement may be the sum or average value of multiple weight measurements output from the multiple load measuring devices 21 when the filler material is applied to the laminated wafer Ws, or after the filler material has been applied to the laminated wafer Ws. The coating amount calculator 22 calculates the first weight measurement and the second weight measurement by calculating the sum or average value of multiple weight measurements.

[0039] The material coating apparatus 1 of this embodiment is equipped with four wafer chucks 25A, 25B. Therefore, the four wafer chucks 25A, 25B hold the edges of the stacked wafers Ws. The four wafer chucks 25A, 25B 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 25A, 25B may be provided, or five or more wafer chucks 25A, 25B may be provided.

[0040] Multiple wafer chucks 25A, 25B are each connected to multiple rotating mechanisms 18. Each rotating mechanism 18 is equipped with an electric motor, but the specific configuration of the rotating mechanisms 18 is not particularly limited. When the multiple rotating mechanisms 18 rotate the multiple wafer chucks 25A, 25B around their respective axes while the multiple wafer chucks 25A, 25B are holding the edges of the stacked wafer Ws, the vertically positioned stacked wafer Ws rotates around the wafer rotation axis Cr.

[0041] Two rotating mechanisms 18 that rotate two of the four wafer chucks 25A, 25B are fixed to the first base 40A. Two other rotating mechanisms 18 that rotate the other two of the four wafer chucks 25A, 25B are fixed to the second base 40B.

[0042] The material coating apparatus 1 includes a first chuck moving mechanism 37A and a second chuck moving mechanism 37B that move a plurality of wafer chucks 25A, 25B and a plurality of rotation mechanisms 18 in a direction toward and toward the wafer rotation axis Cr. The first chuck moving mechanism 37A and the second chuck moving mechanism 37B are composed of actuators such as air cylinders.

[0043] The first chuck moving mechanism 37A is connected to the first base 40A and is configured to move two rotating mechanisms 18 and two wafer chucks 25A and 25B which are fixed to the first base 40A. The second chuck moving mechanism 37B is connected to the second base 40B and is configured to move two rotating mechanisms 18 and two wafer chucks 25A and 25B which are fixed to the second base 40B.

[0044] The chuck movement mechanisms 37A and 37B move the multiple wafer chucks 25A and 25B toward the wafer rotation axis Cr, thereby holding the edges of the stacked wafer Ws with the multiple wafer chucks 25A and 25B. Furthermore, the chuck movement mechanisms 37A and 37B move the multiple wafer chucks 25A and 25B toward the wafer rotation axis Cr, thereby releasing the multiple wafer chucks 25A and 25B from the edges of the stacked wafer Ws.

[0045] In this embodiment, the application of filler material to the edge portion of the stacked wafer Ws is performed while the stacked wafer Ws rotates in a vertical position. More specifically, with the edge portion of the stacked wafer Ws held by the wafer chucks 25A and 25B, the multiple rotation mechanisms 18 rotate the multiple wafer chucks 25A and 25B around their axes, thereby causing the stacked wafer Ws to rotate around the wafer rotation axis Cr. The coating module 3 is located above the stacked wafer Ws. The filler material is discharged from the coating module 3 toward the edge portion of the stacked wafer Ws.

[0046] Figure 6 is an enlarged view from the direction indicated by arrow A in Figure 5. As shown in Figure 6, the laminated wafer Ws applied to this embodiment has a structure in which a first wafer W1 and a second wafer W2 are bonded 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 laminated wafer Ws. The coating module 3 is located above the gap G and fills the gap G with filler material by releasing filler material toward the gap G.

[0047] As shown in Figure 5, the curing apparatus 4 is positioned downstream of the coating module 3 in the rotational direction of the stacked wafer Ws, and is configured to cure the filler applied to the stacked wafer Ws by the coating module 3. The curing of the filler by the curing apparatus 4 is performed while the stacked wafer Ws is rotating. Once the application of the filler is complete, the operation control unit 10 commands the rotation mechanism 18 to stop the rotation of the wafer chucks 25A and 25B, thereby stopping the rotation of the stacked wafer Ws.

[0048] The application of the filler material to the laminated wafer Ws using the material application apparatus 1, as described with reference to Figures 5 and 6, can be performed according to the embodiment shown in the flowchart of Figure 3 or the flowchart of Figure 4.

[0049] Figure 7 is a front view showing yet another embodiment of the material coating apparatus 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 5 and 6, and therefore the redundant description is omitted. In this embodiment, the load measuring device 21 is not incorporated into the wafer chuck 25B but is positioned between a plurality of lower wafer chucks 25B. The load measuring device 21 is fixed on a support member 45. When the stacked wafers Ws are held in the wafer chucks 25A, 25B, the edges of the stacked wafers Ws are away from the load measuring device 21, as shown in Figure 7.

[0050] As shown in Figure 8, after the coating of the filler material from the coating module 3 onto the stacked wafer Ws is complete, and before the weight of the stacked wafer Ws is measured, the operation control unit 10 commands the rotation mechanism 18 to stop the rotation of the multiple wafer chucks 25A, 25B, thereby stopping the rotation of the stacked wafer Ws. Furthermore, the operation control unit 10 commands the chuck movement mechanisms 37A, 37B to move the multiple wafer chucks 25A, 25B slightly away from the wafer rotation axis Cr. As a result, the edge portion of the stacked wafer Ws is placed on the load measuring device 21. The load measuring device 21 can measure the weight of the stacked wafer Ws. The load measuring device 21 is electrically connected to the coating amount calculator 22. The load measuring device 21 measures the weight of the stacked wafer Ws, and the measured weight is transmitted from the load measuring device 21 to the coating amount calculator 22.

[0051] The coating amount calculator 22 is configured to calculate the amount of filler applied to the laminated wafer Ws by acquiring a first weight measurement value output from the load measuring device 21 before the filler is applied to the laminated wafer Ws, acquiring a second weight measurement value output from the load measuring device 21 after the filler is applied to the laminated wafer Ws, and subtracting the first weight measurement value from the second weight measurement value.

[0052] Figure 9 is a flowchart showing one embodiment of applying a filler material F to a stacked wafer Ws of filler material using a material coating apparatus 1 described with reference to Figures 7 and 8. In step 301, the stacked wafer Ws is transported to the wafer holding unit 2 by a transport robot (not shown). The chuck moving mechanisms 37A and 37B move the multiple wafer chucks 25A and 25B toward the wafer rotation axis Cr, and the multiple load measuring devices 21 incorporated in the multiple lower wafer chucks 25B support the edges of the stacked wafer Ws. The multiple upper wafer chucks 25A are in contact with the edges of the stacked wafer Ws but do not hold the edges of the stacked wafer Ws.

[0053] In step 302, the load measuring device 21 outputs a first weight measurement. The coating amount calculator 22 obtains the first weight measurement from the load measuring device 21. In step 303, the operation control unit 10 commands the rotation mechanism 18 to rotate the multiple wafer chucks 25A, 25B and the stacked wafer Ws using the rotation mechanism 18, and simultaneously commands the coating module 3 to coat the edges of the stacked wafer Ws with the filler material F.

[0054] In step 304, the operation control unit 10, after a predetermined time has elapsed, issues a command to the coating module 3 to complete the application of the filler material F to the edges of the stacked wafer Ws. Furthermore, the operation control unit 10 issues a command to the rotation mechanism 18 to stop the rotation of the stacked wafer Ws. In step 305, the motion control unit 10 commands the chuck movement mechanisms 37A and 37B to move the multiple wafer chucks 25A and 25B slightly away from the wafer rotation axis Cr. As a result, the edges of the stacked wafers Ws are placed on the load measuring device 21. In step 306, the load measuring device 21 outputs the second weight measurement value. The coating amount calculator 22 obtains the second weight measurement value from the load measuring device 21. In step 307, the coating amount calculator 22 calculates (determines) the amount of filler F coated on the laminated wafer Ws by subtracting the first weight measurement from the second weight measurement.

[0055] 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. [Explanation of Symbols]

[0056] Ws multilayer wafer F Filling material 1. Material coating device 2. Wafer holding section 3. Coating Module 4 Curing equipment 10 Operation Control Unit 12 Wafer Stages 15 Rotation axis 18 Rotation mechanism 21 Load measuring instrument 22 Application amount calculator 25A Upper wafer chuck 25B Lower wafer chuck 37A First chuck movement mechanism 37B Second Chuck Movement Mechanism 40A Base Unit 1 40B 2nd base 45 Support member

Claims

1. A material coating apparatus for applying a filler to the edge portion of a stacked wafer, A wafer holding section for holding the stacked wafers, A rotation mechanism that rotates the wafer holding portion to rotate the stacked wafer around a predetermined wafer rotation axis, A coating module for applying a filler to the edge portion of the stacked wafer on the wafer holding portion which is rotated by the rotation mechanism, A load measuring device for measuring the weight of the stacked wafer, A material coating apparatus comprising a coating amount calculator that acquires a first weight measurement value output from the load measuring device before the filler material is coated on the laminated wafer, acquires a second weight measurement value output from the load measuring device when the filler material is coated on the laminated wafer or after the filler material has been coated on the laminated wafer, and calculates the amount of the filler material coated on the laminated wafer by subtracting the first weight measurement value from the second weight measurement value.

2. The material coating apparatus according to claim 1, wherein the load measuring device supports the wafer holding portion.

3. The wafer holding section comprises a plurality of roller chucks, The material coating apparatus according to claim 1, wherein the load measuring device is a plurality of load measuring devices that each support the plurality of roller chucks.

4. The wafer holding section comprises a plurality of upper roller chucks and a plurality of lower roller chucks that hold the stacked wafers in a vertical position. The material coating apparatus according to claim 1, wherein the load measuring device is a plurality of load measuring devices attached to each of the plurality of lower roller chucks.

5. The wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks that hold the stacked wafers in a vertical position. The material coating apparatus according to claim 1, wherein the load measuring device is positioned between the plurality of lower roller chucks.

6. The aforementioned coating amount calculator is The second weight measurement value output from the load measuring device is obtained when the filler material is applied to the laminated wafer. The amount of the filler applied to the laminated wafer is calculated by subtracting the first weight measurement from the second weight measurement. The material coating apparatus according to claim 1, configured to determine a coating endpoint when the amount of the filler reaches a predetermined filling threshold.

7. A material coating method for applying a filler to the edge portion of a stacked wafer, The stacked wafer is held by the wafer holding unit, By rotating the wafer holding part using the rotation mechanism, the stacked wafer is rotated around a predetermined wafer rotation axis. A filler material is applied to the edge of the rotating stacked wafer from a coating module. Before the filler is applied to the laminated wafer, a first weight measurement value is obtained from a load measuring device that measures the weight of the laminated wafer. When the filler is applied to the laminated wafer, or after the filler has been applied to the laminated wafer, the second weight measurement value output from the load measuring device is acquired. A material coating method for calculating the amount of filler applied to the laminated wafer by subtracting the first weight measurement from the second weight measurement.

8. The material coating method according to claim 7, wherein the load measuring device supports the wafer holding portion.

9. The wafer holding section comprises a plurality of roller chucks, The material application method according to claim 7, wherein the load measuring device is a plurality of load measuring devices each supporting the plurality of roller chucks.

10. The wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks that hold the stacked wafers in a vertical position. The material application method according to claim 7, wherein the load measuring device is a plurality of load measuring devices attached to the plurality of lower roller chucks, respectively.

11. The wafer holding unit comprises a plurality of upper roller chucks and a plurality of lower roller chucks that hold the stacked wafers in a vertical position. The material application method according to claim 7, wherein the load measuring device is positioned between the plurality of lower roller chucks.

12. The second weight measurement is a measurement output from the load measuring device when the filler material is applied to the laminated wafer. The material coating method according to claim 7, further comprising determining a coating endpoint where the amount of the filler reaches a predetermined filling threshold.

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