Method for manufacturing laminate, laminate, and method for processing laminate

Abstract

To provide a method for manufacturing a laminate, the laminate, and a method for processing the laminate that can prevent damage to a supported object while supporting the object via a liquid.SOLUTION: A method for manufacturing a laminate according to the present invention includes an intermediate layer formation step of forming an intermediate layer on the surface of a support substrate, the intermediate layer having a first surface and a second surface opposite the first surface, such that the first surface faces the surface of the support substrate, a first liquid supply step of supplying a first liquid to at least one of the second surface and the surface of a plate-shaped supported object, and a supported object fixation step of fixing the supported object to the support substrate via the intermediate layer and the first liquid by bringing the intermediate layer and the supported object relatively close to each other.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a laminate, a laminate, and a method for processing a laminate. [Background technology]

[0002] Device chips to be incorporated into various electronic devices are manufactured, for example, by the following procedure. First, the surface of a wafer made of a semiconductor such as silicon is divided into multiple regions by multiple planned division lines called streets, and devices such as electronic circuits are formed in each region. Next, the back side of the wafer is ground so that the wafer has a predetermined thickness, and then the wafer is cut along the streets. This divides the wafer into each region, and device chips are obtained.

[0003] When a wafer is subjected to the above-mentioned cutting or other processing, the wafer is generally supported by a support frame to improve ease of handling. For example, Patent Document 1 discloses a structure in which a wafer before cutting is fixed to a resin sheet and an annular frame is fixed to the outer periphery of the resin sheet. The resin sheet and the wafer are fixed via a liquid (pure water).

[0004] Specifically, when a wafer is pressed against a resin sheet with a liquid interposed between the wafer and the resin sheet, air escapes from minute recesses on the upper surface of the resin sheet, and the liquid penetrates into these recesses. Then, the resin sheet and the wafer are tightly attached by external atmospheric pressure, thereby fixing the wafer to the resin sheet. This method allows the wafer and resin sheet to be fixed without using an adhesive layer.

[0005] Furthermore, when the wafer is fixed to the resin sheet using this method, cavitation can be generated in the liquid between the resin sheet and the wafer by, for example, applying vibration to the resin sheet, which increases the pressure in the region between the resin sheet and the wafer, making it easier to peel the wafer from the resin sheet. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-96078 Summary of the Invention [Problem to be solved by the invention]

[0007] When grinding the backside of a wafer, the front side of the wafer is held by the chuck table of the grinding machine, and the chuck table is rotated while a grinding wheel is pressed against the backside of the wafer. When the wafer becomes thin in this way, subsequent transportation and processing often become difficult. Therefore, before grinding the wafer, for example, a support substrate with a certain degree of hardness is fixed to the wafer.

[0008] However, in this case, if the method of Patent Document 1, in which the wafer and the support substrate are fixed via a liquid, is adopted, the liquid may flow, causing the wafer and the support substrate to come into contact during grinding, etc., and the wafer, which is the supported object, may be damaged.

[0009] Therefore, an object of the present invention is to provide a method for manufacturing a laminate, a laminate, and a method for processing a laminate that can support an object via a liquid while preventing damage to the object. [Means for solving the problem]

[0010] According to one aspect of the present invention, there is provided a method for manufacturing a laminate, comprising: an intermediate layer formation step of forming an intermediate layer on the surface of a support substrate, the intermediate layer having a first surface and a second surface opposite the first surface, so that the first surface faces the surface of the support substrate; a first liquid supply step of supplying a first liquid to at least one of the second surface and the surface of a plate-shaped supported object; and a supported object fixation step of fixing the supported object to the support substrate via the intermediate layer and the first liquid by bringing the intermediate layer and the supported object relatively close to each other.

[0011] Preferably, the intermediate layer formation process includes a second liquid supply process of supplying a second liquid to at least one of the surface and the first surface of the support substrate, and an intermediate layer fixing process of fixing the intermediate layer to the support substrate via the second liquid by bringing the support substrate and the intermediate layer relatively close to each other.

[0012] Preferably, the intermediate layer fixing step includes a pressurizing step of pressurizing at least one of the support substrate and the intermediate layer in a direction in which the support substrate and the intermediate layer approach each other, and the pressurizing step includes a first pressurizing step of pressurizing at least one of the support substrate and the intermediate layer with a first pressure, and a second pressurizing step of pressurizing at least one of the support substrate and the intermediate layer with a second pressure smaller than the first pressure after the first pressurizing step.

[0013] According to another aspect of the present invention, there is provided a method for manufacturing a laminate, comprising: an intermediate layer formation step of forming an intermediate layer on the surface of a plate-shaped supported object, the intermediate layer having a first surface and a second surface opposite the first surface, so that the second surface faces the surface of the supported object; a first liquid supply step of supplying a first liquid to at least one of the first surface and the surface of a supporting substrate; and a supported object fixation step of fixing the supported object to the supporting substrate via the intermediate layer and the first liquid by bringing the intermediate layer and the supporting substrate relatively close to each other.

[0014] Preferably, the supported object fixing step includes a pressurizing step of pressurizing at least one of the support substrate and the supported object in a direction in which the support substrate and the supported object approach each other, and the pressurizing step includes a first pressurizing step of pressurizing at least one of the supported object and the support substrate with a first pressure, and a second pressurizing step of pressurizing at least one of the supported object and the support substrate with a second pressure smaller than the first pressure after the first pressurizing step.

[0015] Preferably, the intermediate layer forming step or the supported object fixing step is carried out under vacuum.

[0016] Furthermore, according to yet another aspect of the present invention, there is provided a laminate comprising a plate-shaped supported object, a support substrate that supports the supported object, an intermediate layer disposed between the supported object and the support substrate, and a liquid present in at least some or all of the space between the intermediate layer and the supported object and between the support substrate and the intermediate layer.

[0017] Preferably, the intermediate layer comprises a fiber or a resin.

[0018] Preferably, the liquid is pure water.

[0019] Preferably, the material of the support substrate is a semiconductor or a ceramic.

[0020] Preferably, the supported object is a semiconductor device substrate having a first surface on which a device is formed and a second surface opposite to the first surface, and the intermediate layer is disposed on the first surface side.

[0021] According to another aspect of the present invention, there is provided a method for processing a laminate, comprising a separation step of separating the support substrate from the laminate, and further comprising a modification step, prior to the separation step, of modifying at least a portion of the intermediate layer by irradiating the intermediate layer with a laser beam. [Effects of the Invention]

[0022] According to the present invention, a laminate can be obtained in which an intermediate layer is provided between the support substrate and the supported object in addition to a liquid layer made of liquid. Therefore, even if the liquid constituting the liquid layer flows, the supported object and the support substrate do not come into contact. Therefore, it is possible to provide a laminate manufacturing method, a laminate, and a laminate processing method that can support the supported object via the liquid while preventing damage to the supported object. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a side view schematically showing the structure of a laminate according to a first embodiment. [Figure 2]FIG. 2 is a perspective view of the supported object. [Figure 3] FIG. 3 is a flowchart of the method for producing a laminate according to the first embodiment. [Figure 4] Figure 4(A) is a side view schematically showing the support substrate and liquid layer after the liquid supply process has been carried out, Figure 4(B) is a side view schematically showing the support substrate, liquid layer and intermediate layer after the intermediate layer fixing process has been carried out, Figure 4(C) is a side view schematically showing the support substrate, liquid layer and intermediate layer after the liquid supply process has been carried out, and Figure 4(D) is a side view schematically showing the support substrate, liquid layer, intermediate layer and supported object after the supported object fixing process has been carried out. [Figure 5] FIG. 5 is a side view schematically showing the structure of the laminate according to the second embodiment. [Figure 6] FIG. 6 is a flowchart of a method for producing a laminate according to the second embodiment. [Figure 7] Figure 7(A) is a side view schematically showing the support substrate and resin layer after the resin application process has been carried out, Figure 7(B) is a side view schematically showing the support substrate and intermediate layer after the intermediate layer fixing process has been carried out, Figure 7(C) is a side view schematically showing the support substrate, intermediate layer and liquid layer after the liquid supply process has been carried out, and Figure 7(D) is a side view schematically showing the support substrate, intermediate layer, liquid layer and supported object after the supported object fixing process has been carried out. [Figure 8] FIG. 8 is a side view schematically showing the structure of the laminate according to the third embodiment. [Figure 9] FIG. 9 is a flowchart of a method for processing a laminate. [Figure 10] Figure 10(A) is a side view schematically showing the laminate after the thinning process has been performed, Figure 10(B) is a side view schematically showing the supported object and intermediate layer in the modification process, Figure 10(C) is a side view schematically showing the intermediate layer and supported object in the intermediate layer separation process, and Figure 10(D) is a view schematically showing the side of the supported object after the intermediate layer separation process has been performed. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a side view schematically showing the structure of a laminated body 11 according to a first embodiment. As shown in Fig. 1, the laminated body 11 has a supported object 21.

[0025] FIG. 2 is a perspective view of the supported object 21. As shown in FIG. 2, the supported object 21 is a disk-shaped semiconductor device substrate made of a semiconductor material such as silicon (Si), silicon carbide (SiC), or gallium arsenide (GaAs). That is, the supported object 21 is configured in a disk shape having a circular first surface (front surface) 21a and a circular second surface (back surface) 21b opposite to the first surface 21a. The thickness of the supported object 21 is, for example, 500 μm or more and 1000 μm or less. However, the shape, material, and thickness of the supported object 21 are not limited to these. For example, the supported object 21 may be configured in a rectangular shape in a plan view seen from a direction perpendicular to the first surface 21a.

[0026] 2, a notch 21c is formed in part of the outer periphery (peripheral edge) of supported object 21 to indicate the crystal orientation of supported object 21. Note that an orientation flat may be formed in supported object 21 instead of notch 21c. Furthermore, supported object 21 does not necessarily have to be formed with notch 21c or orientation flat.

[0027] A plurality of linear streets 23 having a predetermined width are set in a grid pattern on the first surface 21a of the supported object 21. The first surface 21a is divided into a plurality of regions by the streets 23. A device 25 such as an IC (Integrated Circuit) is provided in each of the plurality of regions. However, the streets 23 and devices 25 do not necessarily have to be provided on the first surface 21a.

[0028] As shown in FIG. 1, the laminate 11 has a support substrate 13. The support substrate 13 has the same shape as the supported object 21. That is, in this embodiment, the support substrate 13 has a circular first surface (front surface) 13a and a circular second surface (back surface) 13b opposite to the first surface 13a. The thickness of the support substrate is, for example, 500 μm or more and 1000 μm or less. However, the shape and thickness of the support substrate 13 are not limited to these. For example, if the supported object 21 is rectangular in a plan view, the support substrate 13 is also rectangular in a plan view seen from a direction perpendicular to the first surface 13a.

[0029] The support substrate 13 is used to facilitate handling of the supported object 21, and is made of a material having a certain degree of hardness. Specifically, the support substrate 13 is made of a material selected from semiconductor materials, ceramics, and the like. Examples of semiconductor materials include silicon, silicon carbide, and gallium arsenide. Examples of ceramics include quartz glass containing SiO2 as the main component, sapphire containing Al2O3 as the main component, and rare earth oxides. Examples of rare earth oxides include yttrium aluminate (Y3Al5O 12 ) and yttrium oxide (Y2O3) and the like that can transmit light are preferred.

[0030] Furthermore, the support substrate 13 may be made of a resin. Examples of resins include light-transmitting resins. Specific examples of light-transmitting resins include acrylic resin (PMMA), polycarbonate (PC), polystyrene resin (PS), acrylonitrile-styrene resin (AS), and silicone resin. However, the material of the support substrate 13 is not limited to these.

[0031] The laminate 11 has an intermediate layer 17 provided between the supported object 21 and the support substrate 13. The intermediate layer 17 has the same shape as the supported object 21 and the support substrate 13. That is, the intermediate layer 17 of this embodiment has a circular first surface 17a and a second surface 17b opposite to the first surface 17a. In FIG. 1 , the first surface 17a is disposed on the first surface 13a side of the support substrate 13, and the second surface 17b is disposed on the first surface 21a side of the supported object 21.

[0032] However, the shape and arrangement of intermediate layer 17 are not limited to these. For example, first surface 17a of intermediate layer 17 may be arranged on the side of first surface 21a of supported object 21, and second surface 17b may be arranged on the side of first surface 13a of support substrate 13. Furthermore, if supported object 21 and support substrate 13 are configured to have a rectangular shape in a planar view, intermediate layer 17 will also be configured to have a rectangular shape in a planar view seen from a direction perpendicular to first surface 17a.

[0033] Specific examples of materials for the intermediate layer 17 include paper containing natural fibers, woven or nonwoven fabric containing natural or synthetic fibers, and resin. Examples of resin include water-soluble resins such as polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), and water-insoluble resins such as polyolefin (PO) and polyethylene terephthalate (PET). Furthermore, the intermediate layer 17 may be made of a cured product of a curable resin. Examples of curable resins include photocurable resins and thermosetting resins.

[0034] The thickness of intermediate layer 17 is, for example, 5 μm or more and 50 μm or less. Furthermore, when a structure (such as a bump or a TEG (Test Elementary Group)) is formed on first surface 21a of supported object 21, the thickness of intermediate layer 17 is preferably set so that the structure is completely buried in intermediate layer 17. In other words, when a structure is formed on first surface 21a of supported object 21, the thickness of intermediate layer 17 is set to a value greater than the height of the structure (the distance from first surface 21a to the highest part of the structure) in the range of 5 μm or more and 50 μm or less. However, the thickness of intermediate layer 17 is not limited to these values.

[0035] The laminate 11 has a liquid layer 15 disposed between the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17. The laminate 11 also has a liquid layer 19 disposed between the first surface 21a of the supported object 21 and the second surface 17b of the intermediate layer 17. The presence of the liquid layer 15 and the liquid layer 19 between the support substrate 13 and the supported object 21 makes it possible to easily separate the support substrate 13 from the supported object 21 later.

[0036] There are no limitations on the liquids that make up liquid layer 15 and liquid layer 19, but for example, liquid layer 15 and liquid layer 19 are preferably made of pure water. Note that pure water refers to water with an electrical resistivity of 0.1 MΩ cm or more. Furthermore, the thickness of liquid layer 15 and liquid layer 19 is less than 1 micron. Note that the composition and thickness of liquid layer 15 are not limited to these.

[0037] Note that the liquid layer 15 does not have to be present so as to fill the entire gap between the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17, but the liquid may be present only in a portion of the gap between the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17. In other words, instead of the entire first surface 13a of the support substrate 13 and the entire first surface 17a of the intermediate layer 17 being in contact with the liquid, only a portion of the first surface 13a of the support substrate 13 and a portion of the first surface 17a of the intermediate layer 17 may be in contact with the liquid.

[0038] A fine uneven structure may exist on the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17. Due to this fine uneven structure, when the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17 are brought into contact with each other, a gap may be formed between the first surface 13a of the support substrate 13 and the first surface 17a of the intermediate layer 17. A liquid may exist in this gap.

[0039] The same applies to the liquid layer 19 disposed between the first surface 21a of the supported object 21 and the second surface 17b of the intermediate layer 17. In other words, the liquid layer 19 does not have to be present so as to fill the entire gap between the first surface 21a of the supported object 21 and the second surface 17b of the intermediate layer 17, and the liquid may be present only in a portion of the gap between the first surface 21a of the supported object 21 and the second surface 17b of the intermediate layer 17.

[0040] In this embodiment, an intermediate layer 17 is disposed between the supported object 21 and the support substrate 13 so that the supported object 21 and the support substrate 13 do not come into contact even if the liquids constituting the liquid layer 15 and the liquids constituting the liquid layer 19 flow. Therefore, even if the liquids constituting the liquid layer 15 and the liquid layer 19 flow, the supported object 21 does not come into direct contact with the hard support substrate 13, preventing damage to the supported object 21. Because the liquids constituting the liquid layer 15 and the liquid layer 19 may come into contact with the supported object 21 when they flow, the intermediate layer 17 is made of the aforementioned material that is soft to a certain extent so that the supported object 21 will not be damaged even if it comes into contact with the supported object 21.

[0041] Next, a method for manufacturing the above-described laminate 11 will be described. Fig. 3 is a flowchart of the method for manufacturing the laminate 11 according to the first embodiment. As shown in Fig. 3, the method for manufacturing the laminate 11 according to the first embodiment includes a liquid supplying step S1, an intermediate layer fixing step S2, a liquid supplying step S3, and a supported object fixing step S4. The liquid supplying step S1 and the intermediate layer fixing step S2 are collectively referred to as an intermediate layer forming step S10.

[0042] 4(A) is a side view schematically showing the support substrate 13 and the liquid layer 15 after the liquid supplying step S1 has been performed. As shown in FIG. 4(A), in the liquid supplying step S1, a liquid is supplied to the first surface 13a of the support substrate 13, and the liquid layer 15 is formed.

[0043] The liquid is supplied to the support substrate 13 using, for example, a liquid supply device. The liquid supply device includes, for example, a tank that stores the liquid, a nozzle, and a pipe that connects the tank and the nozzle. The nozzle is disposed above the first surface 13a of the support substrate 13, and the liquid stored in the tank is ejected onto the first surface 13a through the pipe and the nozzle, thereby supplying the liquid to the first surface 13a of the support substrate 13. The liquid may be dripped near the center of the first surface 13a, or may be sprayed onto the entire surface of the first surface 13a.

[0044] Alternatively, the liquid may be supplied to the first surface 17a of the intermediate layer 17 instead of the first surface 13a of the support substrate 13, thereby forming the liquid layer 15 on the first surface 17a.

[0045] 4(B) is a side view schematically showing the support substrate 13, the liquid layer 15, and the intermediate layer 17 after the intermediate layer fixing step S2 has been performed. As shown in FIG. 4(B), in the intermediate layer fixing step S2, at least one of the support substrate 13 and the intermediate layer 17 moves so that the first surface 17a of the intermediate layer 17 approaches the liquid layer 15. When the first surface 17a of the intermediate layer 17 comes into contact with the liquid layer 15, the intermediate layer 17 and the liquid layer 15 are brought into close contact with each other due to the surface tension of the liquid constituting the liquid layer 15 and / or the atmospheric pressure acting on the support substrate 13 and the intermediate layer 17. As a result, the intermediate layer 17 is fixed to the support substrate 13 via the liquid layer 15.

[0046] The intermediate layer fixing step S2 preferably includes a pressurizing step. For example, after the intermediate layer 17 is arranged so that the first surface 17a of the intermediate layer 17 faces the liquid layer 15, the intermediate layer 17 is pressed toward the support substrate 13, thereby strongly adhering the intermediate layer 17 and the liquid layer 15. As a result, the intermediate layer 17 is firmly fixed to the support substrate 13 via the liquid layer 15.

[0047] In another embodiment, after intermediate layer 17 is arranged so that first surface 17a of intermediate layer 17 faces liquid layer 15, support substrate 13 may be pressed toward intermediate layer 17. This causes strong adhesion between intermediate layer 17 and liquid layer 15, and intermediate layer 17 is firmly fixed to support substrate 13 via liquid layer 15.

[0048] In yet another embodiment, after intermediate layer 17 is disposed so that first surface 17a of intermediate layer 17 faces liquid layer 15, intermediate layer 17 may be pressed toward support substrate 13, and support substrate 13 may be pressed toward intermediate layer 17. This causes strong adhesion between intermediate layer 17 and liquid layer 15, and intermediate layer 17 is firmly fixed to support substrate 13 via liquid layer 15.

[0049] The intermediate layer fixing step S2 may be performed under vacuum (reduced pressure). Specifically, the support substrate 13 on which the liquid layer 15 is formed and the intermediate layer 17 may be placed inside a vacuum chamber, the vacuum chamber may be depressurized, and the vacuum chamber may be opened to the atmosphere, thereby fixing the support substrate 13 and the intermediate layer 17 via the liquid layer 15. The pressure inside the vacuum chamber during depressurization is set to a pressure at which the liquid constituting the liquid layer 15 does not boil at the temperature at which the intermediate layer fixing step S2 is performed. For example, when the liquid is water and the temperature inside the vacuum chamber is 20°C, the pressure inside the vacuum chamber is set to 2 kPa or more and 3 kPa or less.

[0050] Furthermore, the intermediate layer fixing step S2 may include a first pressurizing step and a second pressurizing step. In the first pressurizing step, at least one of the support substrate 13 and the intermediate layer 17 is pressurized at a first pressure so that the first surface 17a of the intermediate layer 17 approaches relatively close to the liquid layer 15. In the subsequent second pressurizing step, at least one of the support substrate 13 and the intermediate layer 17 is pressurized at a second pressure smaller than the first pressure so that the first surface 17a of the intermediate layer 17 approaches relatively close to the liquid layer 15.

[0051] More specifically, in the first pressurizing step, at least one of the support substrate 13 and the intermediate layer 17 is pressurized at a first pressure for a predetermined time. After the predetermined time has elapsed, the pressure applied to at least one of the support substrate 13 and the intermediate layer 17 is reduced from the first pressure to a second pressure, and at least one of the support substrate 13 and the intermediate layer 17 is pressurized at the second pressure for a predetermined time. When the intermediate layer fixing step S2 is performed under vacuum (reduced pressure), the vacuum chamber may be opened to the atmosphere after the first pressurizing step and the second pressurizing step are performed.

[0052] In the first pressurizing step, for example, the first pressure is set to 1 kN or more and 20 kN or less, and the time for which pressure is maintained at the first pressure (first pressurizing time) is set to 10 seconds or more and 30 seconds or less. In the second pressurizing step, for example, the second pressure is set to 100 N or more and 200 N or less, and the time for which pressure is maintained at the second pressure (second pressurizing time) is set to 10 seconds or more and 120 seconds or less. In the first pressurizing step and the second pressurizing step, when at least one of the support substrate 13 and the intermediate layer 17 is pressed, the movement speed of the support substrate 13 and / or the intermediate layer 17 is preferably set to 0.5 μm / s or more and 3 μm / s or less, and more preferably set to 1 μm / s. The time between the first pressurizing step and the second pressurizing step is set to 10 seconds or less. Note that the first pressure, first pressurizing time, second pressure, second pressurizing time, movement speed, and time between the first pressurizing step and the second pressurizing step are not limited to these.

[0053] 4(C) is a side view schematically showing the support substrate 13, liquid layer 15, intermediate layer 17, and liquid layer 19 after the liquid supplying step S3 has been performed. As shown in FIG. 4(C), in the liquid supplying step S3, liquid is supplied to the second surface 17b of the intermediate layer 17, and the liquid layer 19 is formed. The method of supplying the liquid to the second surface 17b is the same as in the liquid supplying step S1 described above. The liquid layer 19 may also be formed on the first surface 21a of the supported object 21.

[0054] 4(D) is a side view schematically showing the support substrate 13, liquid layer 15, intermediate layer 17, liquid layer 19, and supported object 21 after supported object fixing step S4 has been performed. As shown in FIG. 4(D), in supported object fixing step S4, at least one of the supported object 21 and the intermediate layer 17 moves so that the first surface 21a of the supported object 21 approaches the liquid layer 19 formed on the second surface 17b of the intermediate layer 17 relatively. When the first surface 21a of the supported object 21 comes into contact with the liquid layer 19, the first surface 21a of the supported object 21 and the liquid layer 19 are tightly adhered to each other due to the surface tension of the liquid constituting the liquid layer 19 and / or the atmospheric pressure acting on the support substrate 13 and the supported object 21. As a result, the supported object 21 is fixed to the support substrate 13 via the liquid layer 15, intermediate layer 17, and liquid layer 19, and the laminate 11 is formed.

[0055] Like the intermediate layer fixing step S2, the supported object fixing step S4 preferably includes a pressurizing step. For example, after the first surface 21a of the supported object 21 is placed so that it faces the liquid layer 19, the supported object 21 is pressed toward the support substrate 13, thereby firmly adhering the first surface 21a of the supported object 21 to the liquid layer 19. This firmly fixes the supported object 21 to the support substrate 13 via the liquid layer 15, the intermediate layer 17, and the liquid layer 19.

[0056] Also, the support substrate 13 may be pressed toward the supported object 21. Furthermore, the supported object 21 may be pressed toward the support substrate 13, and the support substrate 13 may be pressed toward the supported object 21.

[0057] Like the intermediate layer fixing step S2, the supported object fixing step S4 may be performed under vacuum (reduced pressure). The method and conditions for performing the supported object fixing step S4 under vacuum are the same as those for the intermediate layer fixing step S2. That is, the pressure inside the vacuum chamber during decompression is set to a pressure at which the liquid constituting liquid layer 15 and the liquid constituting liquid layer 19 do not boil at the temperature at which the supported object fixing step S4 is performed. For example, if the liquid is water and the temperature inside the vacuum chamber is 20°C, the pressure inside the vacuum chamber is set to 2 kPa or more and 3 kPa or less.

[0058] The supported object fixing step S4 may include a first pressurizing step and a second pressurizing step, similar to the intermediate layer fixing step S2. The method of fixing the supported object 21 to the support substrate 13 by the first pressurizing step and the second pressurizing step, and the pressure and pressurizing time in the first pressurizing step and the second pressurizing step are the same as those in the intermediate layer fixing step S2.

[0059] Fig. 5 is a side view schematically showing the structure of a laminate 27 according to the second embodiment. As shown in Fig. 5, the laminate 27 according to the second embodiment has a support substrate 13, an intermediate layer 29, a liquid layer 19, and a supported object 21, in this order. In other words, the laminate 27 of the second embodiment does not have anything equivalent to the liquid layer 15 in the laminate 11 of the first embodiment. The configurations of the support substrate 13, the supported object 21, and the liquid layer 19 are the same as those of the first embodiment.

[0060] The intermediate layer 29 has the same configuration as the intermediate layer 17 of the first embodiment. That is, it has a disk shape having a circular first surface 29a and a circular second surface 29b opposite to the first surface 29a. Meanwhile, the first surface 29a of the intermediate layer 29 faces the first surface 13a of the support substrate 13, and the second surface 29b faces the liquid layer 19. However, the shape and arrangement of the intermediate layer 29 are not limited to these. For example, the first surface 29a of the intermediate layer 29 may face the liquid layer 19, and the second surface 19b may face the first surface 13a of the support substrate.

[0061] In this embodiment, the intermediate layer 29 is made of a cured product of a photocurable resin, such as an ultraviolet curable resin.

[0062] Next, a method for manufacturing the above-mentioned laminate 27 will be described. Fig. 6 is a flowchart of the method for manufacturing the laminate 27 according to the second embodiment. As shown in Fig. 6, the method for manufacturing the laminate 27 according to the second embodiment includes a resin application step S21, an intermediate layer fixing step (resin curing step) S22, a liquid supply step S23, and a supported object fixing step S24. The resin application step S21 and the intermediate layer fixing step S22 are collectively referred to as an intermediate layer forming step S31.

[0063] Fig. 7(A) is a side view schematically showing the support substrate 13 and the resin layer 31 after the resin application step S21 has been performed. In the resin application step S21, as shown in Fig. 7(A), a liquid resin (paint) containing a photocurable resin that forms the intermediate layer 29 is applied to the first surface 13a of the support substrate 13 to form a resin layer (coating film) 31. In Fig. 7(A), the resin layer 31 is hatched to distinguish it from the intermediate layer 29, which is obtained by curing the resin layer 31 and will be described later.

[0064] The liquid resin contains a photocurable resin and a solvent for imparting fluidity to the coating material. The coating material is applied to the first surface 13a of the support substrate 13 by, for example, a spin coater. The spin coater includes, for example, a rotatable table, a tank for storing the coating material, a nozzle, and piping connecting the tank and the nozzle. The coating material is dropped onto the first surface 13a of the support substrate 13 held by the table through the nozzle, and the support substrate 13 is rotated at high speed, thereby forming a resin layer 31 on the first surface 13a of the support substrate 13.

[0065] 7(B) is a side view schematically showing the support substrate 13 and the intermediate layer 29 after the intermediate layer fixing step (resin curing step) S22 has been performed. In the intermediate layer fixing step S22, the resin layer 31 applied in the resin application step S21 is irradiated with light (ultraviolet light) from above the resin layer 31, thereby curing the resin layer 31. As a result, the intermediate layer 29 formed by the cured resin layer 31 is fixed to the first surface 13a of the support substrate 13. Note that when the support substrate 13 is made of a light-transmitting material, light can be irradiated onto the resin layer 31 from the support substrate 13 side.

[0066] 7(C) is a side view schematically showing the support substrate 13, intermediate layer 29, and liquid layer 19 after the liquid supplying step S23 has been performed. As shown in FIG. 7(C), in the liquid supplying step S23, liquid is supplied to the second surface 29b of the intermediate layer 29, and the liquid layer 19 is formed. The method of supplying the liquid in the liquid supplying step S23 is the same as in the liquid supplying step S1 of the first embodiment. Note that the liquid layer 19 may be formed on the first surface 21a by supplying the liquid to the first surface 21a of the supported object 21.

[0067] 7(D) is a side view schematically showing the support substrate 13, intermediate layer 29, liquid layer 19, and supported object 21 after supported object fixing step S24 has been performed. Supported object fixing step S24 is performed in the same manner as supported object fixing step S4 in the first embodiment, and supported object 21 is fixed to support substrate 13 via intermediate layer 29 and liquid layer 19. As a result, stacked body 27 is formed.

[0068] 5 may include the intermediate layer 17 described in the first embodiment instead of the intermediate layer 29. In this case, the resin application step S21 shown in Fig. 6 is omitted, and the intermediate layer 17 of the first embodiment is disposed and fixed to the first surface 13a of the support substrate 13 in the intermediate layer fixing step S22. For example, the support substrate 13 and the intermediate layer 17 are fixed to each other via an adhesive such as wax.

[0069] Fig. 8 is a side view schematically showing the structure of a laminate 33 according to the third embodiment. As shown in Fig. 8, the laminate 33 according to the third embodiment has a support substrate 13, a liquid layer 15, an intermediate layer 17, and a supported object 21, in this order. In other words, the laminate 33 of the third embodiment does not have anything equivalent to the liquid layer 19 in the laminate 11 of the first embodiment. The configurations of the support substrate 13, the liquid layer 15, the intermediate layer 17, and the supported object 21 are the same as those of the first embodiment. The method for manufacturing the laminate 33 is also the same as that for manufacturing the laminate 11 of the first embodiment.

[0070] 8 may include the intermediate layer 29 of the second embodiment instead of the intermediate layer 17. In this case, a resin layer 31 is formed on the first surface 21a of the supported object 21. Then, the resin layer 31 is irradiated with light, whereby the intermediate layer 29 is formed on the first surface 21a of the supported object 21.

[0071] Next, a description will be given of a method for processing the above-described laminate 11. Fig. 9 is a flowchart of the method for processing the laminate 11. As shown in Fig. 9, the method for processing the laminate 11 according to this embodiment includes a thinning step S41, a modification step S42, a support substrate separation step S43, and an intermediate layer separation step S44.

[0072] 10(A) is a side view schematically showing the laminate 11 after the thinning step S41 has been performed. In the thinning step S41, the supported object 21 is ground to a predetermined thickness. In FIG. 10(A), the supported object 21 before grinding is shown by a dotted line.

[0073] Grinding is performed by, for example, a grinding device. The grinding device includes, for example, a holding table that holds the laminate 11 and a grinding unit arranged above the holding table. A rotary drive source is connected to the lower part of the holding table. The grinding unit has a spindle whose upper end is connected to the rotary drive source. A grinding wheel having a structure in which multiple grinding stones are arranged on an annular base is attached to the lower end of the spindle.

[0074] With the second surface 13b side of the support substrate 13 held by the holding table, the holding table is rotated, and with the grinding wheel rotating together with the spindle, the grinding stone is pressed against the second surface 21b side of the supported object 21, thereby grinding the second surface 21b side of the supported object 21. Note that the method of thinning the supported object 21 to a predetermined thickness in the thinning step S41 is not limited to grinding.

[0075] Next, the modification step S42 is carried out. Fig. 10(B) is a diagram schematically showing the side surface of the laminate 11 in the modification step S42. As shown in Fig. 10(B), in the modification step S42, the intermediate layer 17 is irradiated with a laser beam 2. Specifically, the positions of the focal point of the laser beam 2 and the laminate 11 are adjusted so that the laser beam 2 is focused near the interface of the intermediate layer 17 with the liquid layer 15 (i.e., near the first surface 17a).

[0076] The types of laser beams include, for example, a UV (Ultra Violet) laser beam having a wavelength in the ultraviolet range (100 nm to 400 nm), a green laser beam having a wavelength around 530 nm, and an IR (Infrared) laser beam having a wavelength in the infrared range (780 nm to 1 mm), etc. The type (wavelength) of the laser beam is appropriately selected from these depending on the material of the support substrate 13, etc.

[0077] Then, the laser beam 2 is scanned in a direction parallel to the first surface 17a of the intermediate layer 17, thereby forming a modified layer 35 near the interface between the liquid layer 15 and the intermediate layer 17. The irradiation conditions, including the irradiation position of the laser beam 2, are adjusted so that the modified layer 35 is appropriately formed in the intermediate layer 17. Note that in this modification step S42, the liquid that constitutes the liquid layer 15 may evaporate due to heat or the like caused by the irradiation of the laser beam 2, and the liquid layer 15 may be lost.

[0078] Next, a support substrate separation step S43 is performed. When the modified layer 35 is formed on the first surface 17a side of the intermediate layer 17, unevenness occurs on the first surface 17a of the intermediate layer 17, and it is thought that the adhesion between the support substrate 13 (liquid layer 15) and the intermediate layer 17 will decrease. Therefore, after the modified layer 35 is formed on the intermediate layer 17, the support substrate 13 and the intermediate layer 17 are moved relatively far apart, so that the intermediate layer 17 can be easily separated from the support substrate 13 (and the liquid layer 15). For example, the support substrate 13 is pulled while the second surface 21b side of the supported object 21 is held by a holding table, and the support substrate 13 (and the liquid layer 15) is separated from the supported object 21 and the intermediate layer 17.

[0079] Next, an intermediate layer separating step S44 is performed. Fig. 10(C) is a side view schematically showing the intermediate layer 17, the liquid layer 19, and the supported object 21 in the intermediate layer separating step S44. Fig. 10(D) is a view schematically showing the side of the supported object 21 after the intermediate layer separating step S44 has been performed.

[0080] 10(C) and 10(D), in the intermediate layer separation step S44, the intermediate layer 17 is separated from the supported object 21. For example, O2 ashing is performed on the intermediate layer 17, and the intermediate layer 17 is removed from the supported object 21, thereby separating the intermediate layer 17 from the supported object 21. In the O2 ashing, oxygen plasma 4 is irradiated onto the intermediate layer 17, causing the intermediate layer 17 to decompose and vaporize, thereby removing the intermediate layer 17 from the supported object 21.

[0081] The method for separating intermediate layer 17 from supported object 21 is not limited to the O2 ashing described above. For example, intermediate layer 17 and supported object 21 can be separated by fixing adhesive tape to first surface 17a of intermediate layer 17 and moving intermediate layer 17 and supported object 21 in a direction that moves them relatively away from each other.

[0082] Furthermore, when the intermediate layer 17 is made of a water-soluble resin, the intermediate layer 17 and the supported object 21 can be separated by supplying water to the intermediate layer 17 to dissolve the water-soluble resin.

[0083] Alternatively, the support substrate 13 and the intermediate layer 17 may be separated by ablating the first surface 17a side of the intermediate layer 17 with a laser beam. Specifically, a laser beam is irradiated onto the intermediate layer 17 near the interface with the liquid layer 15 (i.e., near the first surface 17a) to partially vaporize the intermediate layer 17. This generates bubbles between the intermediate layer 17 and the support substrate 13 (and the liquid layer 15), or causes irregularities on the first surface 17a of the intermediate layer 17, reducing the adhesion between the support substrate 13 (and the liquid layer 15) and the intermediate layer 17. Thereafter, the support substrate separating step S43 described above is performed, thereby separating the support substrate 13 (and the liquid layer 15) from the intermediate layer 17.

[0084] Furthermore, the support substrate 13 and the intermediate layer 17 may be separated by ablating the first surface 13a side of the support substrate 13 with a laser beam. In this case, air bubbles may be generated between the intermediate layer 17 and the support substrate 13 (and the liquid layer 15), or irregularities may be generated on the first surface 13a of the support substrate 13, thereby reducing the adhesion between the support substrate 13 (and the liquid layer 15) and the intermediate layer 17. Thereafter, the support substrate separation step S43 described above is performed, whereby the support substrate 13 (and the liquid layer 15) and the intermediate layer 17 are separated.

[0085] Furthermore, in the intermediate layer separation step S44, the liquid layer 19 is heated to evaporate the liquid that constitutes the liquid layer 19, thereby separating the intermediate layer 17 from the supported object 21. For example, the liquid layer 19 can be heated using a heating device such as a heater. Note that if a laser beam has a wavelength that can pass through the intermediate layer 17 or the supported object 21, a laser beam can be used to heat the liquid layer 19.

[0086] In addition, the modification process S42 in the above-mentioned embodiment can be omitted, and the support substrate 13 and the intermediate layer 17 can be separated in the support substrate separation process S43 by heating the liquid layer 15 and evaporating the liquid that constitutes the liquid layer 15.

[0087] Furthermore, the separation of support substrate 13, intermediate layer 17, and supported object 21 is not limited to the above-described manner. For example, when laminate 11 is immersed in a liquid, the liquid penetrates between support substrate 13 and intermediate layer 17 and between intermediate layer 17 and supported object 21, and the volumes of liquid layer 15 and liquid layer 19 increase.

[0088] This creates gaps between the support substrate 13 and the intermediate layer 17 and between the intermediate layer 17 and the supported object 21, reducing the adhesion therebetween and allowing the support substrate 13, intermediate layer 17, and supported object 21 to be easily separated. In this case, the support substrate 13, intermediate layer 17, and supported object 21 are separated at the same time. That is, the support substrate separation step S43 and the intermediate layer separation step S44 are performed substantially simultaneously. In this case, the modification step S42 is omitted. Furthermore, after immersing the laminate 11 in a liquid, one or both of the support substrate 13 and the supported object 21 may be pulled in directions that move them relatively apart.

[0089] Alternatively, an ultrasonic generator may apply ultrasonic waves to laminate 11. Applying ultrasonic waves to laminate 11 causes cavitation in the liquid of liquid layer 15 and liquid layer 19, generating bubbles in liquid layer 15 and liquid layer 19. This creates gaps between support substrate 13 and intermediate layer 17 and between intermediate layer 17 and supported object 21, reducing the adhesive force between them and allowing support substrate 13, intermediate layer 17, and supported object 21 to be easily separated.

[0090] In this case, the support substrate 13, intermediate layer 17, and supported object 21 are also separated at the same time. That is, the support substrate separation step S43 and the intermediate layer separation step S44 are performed substantially simultaneously. In this case, the modification step S42 is omitted. Note that ultrasonic waves may be applied to the laminate 11 in a liquid such as water.

[0091] Instead of the thinning step S41 described above, another process may be performed on the supported object 21. For example, cutting, polishing, or laser processing may be performed on the supported object 21. Also, an inspection process may be performed on the supported object 21. Furthermore, instead of the thinning step S41, a process of attaching the supported object 21 to a dicing frame may be performed.

[0092] As described above, the laminate manufacturing method, laminate, and laminate processing method according to the embodiments provide a laminate in which an intermediate layer is provided between the support substrate and the supported object in addition to a liquid layer made of liquid. Therefore, even if the liquid constituting the liquid layer flows, the supported object and the support substrate do not come into contact. Therefore, damage to the supported object can be prevented while supporting the supported object via the liquid.

[0093] The structures, methods, and the like according to the above-described embodiments and modifications may be modified and implemented without departing from the scope of the present invention. [Explanation of symbols]

[0094] 11: Laminate 13: Support substrate 13a: 1st side (front) 13b: 2nd side (back side) 15:Liquid layer 17: Middle class 17a: 1st page 17b: 2nd side 19:Liquid layer 21: Supported object 21a: 1st side (front) 21b: 2nd side (back side) 21c: Notch 23: Street 25: Device 27: Laminate 29: Middle class 29a: 1st page 29b: 2nd side 31: Resin layer (coating film) 33: Laminate 35: Modified layer 2: Laser beam 4: Oxygen plasma

Claims

1. an intermediate layer forming step of forming an intermediate layer having a first surface and a second surface opposite to the first surface on a surface of a support substrate such that the first surface faces the surface of the support substrate; a first liquid supplying step of supplying a first liquid to at least one of the second surface and a surface of the plate-shaped supported object; a supported object fixing step of fixing the supported object to the support substrate via the intermediate layer and the first liquid by bringing the intermediate layer and the supported object relatively close to each other.

2. The intermediate layer forming step includes: a second liquid supplying step of supplying a second liquid to at least one of the front surface and the first surface of the support substrate; The method for producing a laminate according to claim 1 , further comprising: an intermediate layer fixing step of fixing the intermediate layer to the support substrate via the second liquid by bringing the support substrate and the intermediate layer relatively close to each other.

3. the intermediate layer fixing step includes a pressurizing step of pressurizing at least one of the support substrate and the intermediate layer in a direction in which the support substrate and the intermediate layer approach each other; The pressurizing step includes: a first pressurizing step of pressing at least one of the support substrate and the intermediate layer with a first pressure; The method for producing a laminate according to claim 2 , further comprising, after the first pressurizing step, a second pressurizing step of pressing at least one of the support substrate and the intermediate layer with a second pressure lower than the first pressure.

4. an intermediate layer forming step of forming an intermediate layer having a first surface and a second surface opposite to the first surface on a surface of a plate-shaped supported object, such that the second surface faces the surface of the supported object; a first liquid supplying step of supplying a first liquid to at least one of the first surface and a surface of a support substrate; a supported object fixing step of fixing the supported object to the support substrate via the intermediate layer and the first liquid by bringing the intermediate layer and the support substrate relatively close to each other.

5. the supported object fixing step includes a pressurizing step of pressurizing at least one of the support substrate and the supported object in a direction in which the support substrate and the supported object approach each other; The pressurizing step includes: a first pressurizing step of applying a first pressure to at least one of the supported object and the supporting substrate; The method for manufacturing a laminate according to claim 4 , further comprising, after the first pressurizing step, a second pressurizing step of pressing at least one of the supported object and the support substrate with a second pressure lower than the first pressure.

6. The method for producing a laminate according to claim 1 or 4, wherein the intermediate layer forming step or the supported object fixing step is carried out under vacuum.

7. A plate-shaped supported object; a support substrate that supports the supported object; an intermediate layer provided between the supported object and the supporting substrate; a liquid present in at least a portion or the entirety of either between the intermediate layer and the supported object or between the supporting substrate and the intermediate layer.

8. The laminate of claim 7 , wherein the intermediate layer comprises a fiber or a resin.

9. The laminate according to claim 7, wherein the liquid is pure water.

10. 10. The laminate according to claim 7, wherein the material of the support substrate is a semiconductor or a ceramic.

11. the supported object is a semiconductor device substrate having a first surface on which a device is formed and a second surface opposite to the first surface, The laminate according to any one of claims 7 to 9, wherein the intermediate layer is disposed on the first surface side.

12. A method for processing a laminate according to any one of claims 7 to 9, comprising: a separation step of separating the support substrate from the laminate; The method for processing a laminate further comprises, before the separating step, a modifying step of modifying at least a portion of the intermediate layer by irradiating the intermediate layer with a laser beam.

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