Protective sheet dispensing apparatus and method of dispensing protective sheets

Abstract

The present application provides a protective sheet arrangement device and a protective sheet arrangement method for arranging a protective sheet on a substrate while controlling the adhesion of the protective sheet to the substrate. The protective sheet arrangement method arranges a protective sheet on the front surface of a substrate, and includes the following steps: a substrate placement step of placing the substrate on a support table of a decompression chamber that is separable into an upper housing and a lower housing and has the support table; a space separation step of separating a space in the decompression chamber into a first chamber and a second chamber by placing the protective sheet so as to face the front surface of the substrate; a decompression step of decompressing the first chamber to a predetermined air pressure and decompressing the second chamber; a protective sheet adhesion step of opening the decompressed second chamber to the atmosphere, thereby causing the protective sheet to adhere to the substrate with a predetermined strength; and a substrate removal step of opening the decompressed first chamber to the atmosphere, separating the lower housing from the upper housing, and removing the substrate with the protective sheet adhered thereto from the decompression chamber.

Description

TECHNICAL FIELD

[0001] The present application relates to a protective sheet attaching apparatus and a protective sheet attaching method for attaching a protective sheet to a front surface of a substrate having unevenness on the front surface. BACKGROUND

[0002] A device chip used in an electronic device such as a mobile phone or a personal computer is formed by thinning a substrate having a plurality of devices attached in parallel from the back surface side by grinding and dividing the substrate for each device. The grinding of the substrate is performed using a grinding apparatus. In the grinding apparatus, the substrate is held by a chuck table in a state where the back surface side is exposed upward, and a grinding tool that moves in a circular orbit is brought into contact with the back surface side of the substrate to grind the substrate. At this time, in order to protect the front surface side of the substrate, a protective tape made of a laminated base material layer and a paste layer is attached to the front surface of the substrate in advance.

[0003] A pattern or the like constituting a device or a wiring is attached to the front surface side of the substrate. In addition, a bump that is an electrode of a device is sometimes formed on the front surface side of the substrate in advance. Therefore, unevenness is formed on the front surface of the substrate due to various patterns or bumps and the like. In the case where the unevenness on the front surface of the substrate has a large difference in level, a protective tape having a thick paste layer is considered to be used so that the unevenness on the front surface of the substrate can be sufficiently absorbed. However, in this case, when the protective tape is peeled from the substrate, residues of the paste layer are easily left in the unevenness, thereby becoming a cause of a defective device chip.

[0004] Therefore, a protective tape having a paste layer only in a region corresponding to a remaining region of the outer periphery of the substrate where no device is formed and having no paste layer in a region corresponding to a device formation region of the substrate where a device is formed has been developed (for example, refer to Patent Documents 1 and 2). However, in this protective tape, the following problem remains: the region to which the protective tape is not attached becomes wide, and thus the fixation to the substrate becomes unstable.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2005-123382

[0006] Patent Document 2: Japanese Patent Application Publication No. 2013-239564

[0007] Therefore, a method of attaching a protective sheet made of resin having no paste layer to a substrate instead of a protective tape having a paste layer is considered. When the protective sheet is placed on the front surface of a substrate having unevenness on the front surface and the protective sheet is heated and softened so that the protective sheet is tightly attached to the unevenness on the front surface of the substrate, the protective sheet can be fixed to the front surface of the substrate. The protective sheet is fixed to a wide region on the front surface of the substrate, and thus the fixation to the substrate does not become unstable. In addition, the protective sheet has no paste layer, and thus no residues of the paste layer remain on the substrate after the protective sheet is peeled from the substrate.

[0008] However, when the protective sheet is firmly attached to the front surface of the substrate, there is a problem that the bump provided on the front surface of the substrate is peeled off from the substrate together with the protective sheet when the protective sheet is peeled off from the substrate. On the other hand, when the attachment of the protective sheet to the front surface of the substrate is weak, there is a problem that the grinding water supplied to the substrate during grinding of the substrate, or the machining chips generated from the substrate, enter between the protective sheet and the substrate. SUMMARY

[0009] The present application has been achieved in view of the above problems, and an object thereof is to provide a protective sheet providing device and a method of providing a protective sheet, which can control the attachment of the protective sheet to a substrate and appropriately provide the protective sheet on the substrate.

[0010] According to one embodiment of the present application, a protective sheet providing device provides a protective sheet to a front surface of a substrate having a concave-convex on the front surface side, characterized by comprising: a decompression chamber which can be separated into an upper housing and a lower housing; a support table which is provided inside the lower housing and on which the substrate is placed; a first decompression unit which is connected to the lower housing; a first atmosphere opening unit which is connected to the lower housing; a second decompression unit which is connected to the upper housing; and a second atmosphere opening unit which is connected to the upper housing, the first decompression unit being capable of decompressing a first chamber in the decompression chamber to a prescribed air pressure, the first chamber being enclosed by the protective sheet and the lower housing which are disposed on the substrate placed on the support table and are sandwiched by the upper housing and the lower housing, the second decompression unit being capable of decompressing a second chamber in the decompression chamber, the second chamber being enclosed by the protective sheet and the upper housing which are disposed on the substrate placed on the support table and are sandwiched by the upper housing and the lower housing, the second atmosphere opening unit being capable of attaching the protective sheet to the front surface of the substrate with a prescribed strength by opening the decompressed second chamber to the atmosphere, and the first atmosphere opening unit being capable of separating the upper housing and the lower housing of the decompression chamber by opening the first chamber to the atmosphere after opening the second chamber to the atmosphere by the second atmosphere opening unit, and taking out the substrate attached to the protective sheet from the decompression chamber.

[0011] It is preferable that the protective sheet providing device has a protective sheet support portion which supports the protective sheet disposed on the substrate placed on the support table around the support table.

[0012] Further, it is preferable that the protective sheet providing device has a heating unit which heats one or both of the protective sheet and the substrate.

[0013] Further, according to another aspect of the present application, there is provided a method of arranging a protective sheet, the method of arranging the protective sheet being characterized by comprising: a substrate placement step of placing a substrate on a support table provided inside a decompression chamber in a state in which an upper case and a lower case of the decompression chamber, which is capable of being separated into the upper case and the lower case, are separated, the substrate facing upward, wherein the decompression chamber has the support table on which the substrate is placed, a first decompression unit and a first atmosphere opening unit that are both connected to the lower case, and a second decompression unit and a second atmosphere opening unit that are both connected to the upper case; a space separation step of placing a protective sheet on the substrate and the lower case with the protective sheet facing the substrate placed on the support table, sandwiching the protective sheet with the lower case and the upper case and integrating the lower case and the upper case to separate a space inside the decompression chamber into a first chamber surrounded by the lower case and the protective sheet and a second chamber surrounded by the upper case and the protective sheet; a decompression step of decompressing the first chamber to a prescribed air pressure by the first decompression unit and decompressing the second chamber by the second decompression unit; a protective sheet adhesion step of opening the decompressed second chamber to the atmosphere by the second atmosphere opening unit to cause the protective sheet to adhere to the substrate at a prescribed strength so as to follow the concave-convex surface of the substrate; and a substrate removal step of opening the decompressed first chamber to the atmosphere by the first atmosphere opening unit after the protective sheet adhesion step, separating the lower case and the upper case, and removing the substrate to which the protective sheet adheres from the decompression chamber.

[0014] Preferably, the protective sheet is a resin sheet containing a polyolefin or a polyester.

[0015] Further, preferably, the method of arranging the protective sheet further comprises a heating step of heating one or both of the protective sheet and the substrate after the space separation step and before the substrate removal step.

[0016] In the method of arranging a protective sheet and the method of arranging a protective sheet according to one embodiment of the present application, a substrate is placed on a support table provided inside a decompression chamber, and a protective sheet is arranged on the substrate. Then, a first chamber on a lower side of the protective sheet and a second chamber on an upper side of the protective sheet are decompressed. Then, the second chamber is opened to the atmosphere to cause the protective sheet to adhere to the substrate.

[0017] Here, the strength of the adhesion of the protective sheet to the substrate is determined by the amount of force with which the protective sheet is pressed toward the substrate when the second chamber is opened to the atmosphere. The amount of force is determined by the air pressure of the first chamber after decompression. Therefore, by adjusting the air pressure of the first chamber decompressed by the first decompression unit, the adhesion of the protective sheet to the substrate can be controlled to a desired state.

[0018] For example, the adhesion of the protective sheet to the substrate can be controlled in such a manner that the protrusions are not peeled off together with the protective sheet when the protective sheet is peeled off from the substrate provided with the protrusions on the front surface. In addition, the adhesion of the protective sheet to the substrate can be controlled in such a manner that the grinding water supplied to the substrate or the like during grinding or the machining chips generated from the substrate or the like do not enter between the protective sheet and the substrate.

[0019] Therefore, according to one embodiment of the present application, a protective sheet providing device and a method of providing a protective sheet are provided, which can control the adhesion of the protective sheet to the substrate and appropriately provide the protective sheet to the substrate. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a perspective view schematically showing a substrate.

[0021] Figure 2 (A) of FIG. 1 is a cross-sectional view schematically showing a protective sheet providing device, Figure 2 (B) of FIG. 1 is a cross-sectional view schematically showing a substrate placing step.

[0022] Figure 3 (A) of FIG. 2 is a cross-sectional view schematically showing a spatial separation step, Figure 3 (B) of FIG. 2 is a cross-sectional view schematically showing a pressure reduction step.

[0023] Figure 4 (A) of FIG. 3 is a cross-sectional view schematically showing a protective sheet adhesion step, Figure 4 (B) of FIG. 3 is a cross-sectional view schematically showing a substrate carrying-out step.

[0024] Figure 5 (A) of FIG. 4 is a cross-sectional view schematically showing a protective sheet strongly adhered to the front surface of a substrate, Figure 5 (B) of FIG. 4 is a cross-sectional view schematically showing a protective sheet weakly adhered to the front surface of a substrate.

[0025] Figure 6 is a flowchart schematically showing a flow of each step of a method of providing a protective sheet.

[0026] REFERENCE NUMERALS

[0027] 1: substrate; 1a: front surface; 1b: back surface; 1c: side surface; 3: division- scheduled line; 5: device; 7: bump; 9: device formation region; 11: outer peripheral remaining region; 13: protective sheet; 2: protective sheet provision device; 4: decompression chamber; 6: lower housing; 8: upper housing; 6a, 8a: opening; 6b, 8b: chamber; 10: support table; 10a: support surface; 10b: frame; 12: protective sheet support portion; 14: heating unit; 16a, 16b: decompression unit; 18a, 18b: decompression path; 20a, 20b: suction source; 22a, 22b: switching valve; 24a, 24b: air pressure gauge; 26a, 26b: atmosphere opening unit; 28a, 28b: air supply path; 30a, 30b: switching valve. DETAILED DESCRIPTION

[0028] An embodiment of one mode of the present application will be described with reference to the drawings. In the protective sheet provision device and the provision method of the protective sheet of the present embodiment, a protective sheet is provisioned on the front surface of a substrate such as a semiconductor wafer on which a plurality of devices are formed on the front surface. First, a substrate to which a protective sheet is to be provisioned on the front surface will be described. Figure 1 is a perspective view schematically showing a substrate 1. In Figure 2 includes a cross-sectional view schematically showing the substrate 1 in (B) and the like. Also, in (A) and the like of Figure 5 includes a cross-sectional view schematically showing the front surface 1a side of the substrate 1 enlarged.

[0029] The substrate 1 is, for example, a wafer formed of a material such as Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or another semiconductor. Alternatively, the substrate 1 is a substantially circular plate-like substrate or the like composed of a material such as sapphire, glass, quartz, or the like. The glass is, for example, alkali glass, non-alkali glass, soda-lime glass, lead glass, borosilicate glass, quartz glass, or the like.

[0030] A plurality of division-scheduled lines 3 intersecting with each other are provided on the front surface 1a of the substrate 1. A device 5 such as an IC (Integrated Circuit), LSI (Large Scale Integration), or the like is formed in each region divided by the division-scheduled lines 3. When the substrate 1 is thinned by polishing from the back surface 1b side and is divided along the division-scheduled lines 3, individual device chips can be formed.

[0031] A plurality of projections called bumps 7 formed of metal are provided on the front surface la of the substrate 1. The bumps 7 are electrically connected to the devices 5, respectively, and function as electrodes when inputting and outputting electric signals to the devices 5 when the substrate 1 is divided to form device chips. The bumps 7 are formed of, for example, a metal material such as gold, silver, copper, or aluminum. However, the bumps 7 can not be provided on the front surface la of the substrate 1.

[0032] A region of the front surface la of the substrate 1 around the outer periphery of the region in which the devices 5 are formed is called an outer periphery remaining region 11. The devices 5 are not formed in the outer periphery remaining region 11 of the front surface la of the substrate 1, and the bumps 7 as electrodes of the devices 5 are not formed either. A region of the front surface la of the substrate 1 surrounded by the outer periphery remaining region 11 is called a device formation region 9. The device formation region 9 of the front surface la of the substrate 1 is not flat but has unevenness caused by each pattern constituting the devices 5 or the bumps 7.

[0033] In addition, the substrate 1 to which the protective sheet is attached is not limited to this. For example, it can be a package substrate formed by sealing a plurality of devices arranged side by side in a plane with sealing resin. When the package substrate is thinned by grinding the sealing resin on the back surface side of the package substrate and the package substrate is divided for each device, each device chip sealed with the sealing resin of a prescribed thickness can be formed. Bumps as electrodes of each device are formed on the front surface of the package substrate, and thus the front surface of the package substrate is also not flat but has unevenness.

[0034] When the substrate 1 is ground and thinned from the back surface lb side by the grinding device, the device chip thinned to a prescribed thickness is obtained when the substrate 1 is divided. When the substrate 1 is ground from the back surface lb side, the protective sheet is attached to the front surface la side in advance in order to protect the front surface la side. When the substrate 1 to which the protective sheet is attached on the front surface la is carried into the grinding device, the substrate 1 is appropriately supported on the support table with the protective sheet interposed therebetween.

[0035] Next, the protective sheet attaching device of the present embodiment will be described. Figure 2 FIG. 1 is a cross-sectional view schematically showing the protective sheet attaching device 2. The protective sheet attaching device 2 has a decompression chamber 4 that can be separated into an upper housing 8 and a lower housing 6.

[0036] For example, the upper housing 8 can be raised and lowered. The opening 6a of the lower housing 6 and the opening 8a of the upper housing 8 are the same shape. When the upper housing 8 is lowered to the lower housing 6 in a manner that the openings 6a, 8a overlap each other, a space that is shut off from the outside can be formed inside the upper housing 8 and the lower housing 6. In addition, each of the openings 6a, 8a is larger than the substrate 1, and the substrate 1 can be housed in the space inside the decompression chamber 4.

[0037] A support table 10 that supports the substrate 1 is provided in the lower case 6. The upper surface of the support table 10 is a flat support surface 10a that supports the substrate 1. A frame 10b having a diameter corresponding to the diameter of the substrate 1 is fixed to the support surface 10a. The substrate 1 is placed on the area of the support surface 10a surrounded by the frame 10b.

[0038] The height of the support table 10 is adjusted so that the front surface la of the substrate 1 is substantially the same as the height of the opening 6a of the lower case 6 or the opening 6a is slightly higher than the front surface la of the substrate 1 when the substrate 1 is placed on the support surface 10a. Alternatively, the height of the support table 10 is adjusted so that the opening 6a of the lower case 6 is higher than the front surface la of the substrate 1. In these cases, when the protective sheet 13 is made to adhere to the substrate 1 as described later, the protective sheet 13 is less likely to unnecessarily expand to adhere to the side surface lc of the substrate 1 or the like.

[0039] A protective sheet support portion 12 that supports the protective sheet 13 provided on the substrate 1 placed on the support table 10 around the support table 10 can be provided inside the lower case 6. The height of the upper surface of the protective sheet support portion 12 is higher than the height of the front surface la of the substrate 1 placed on the support table 10. When the protective sheet support portion 12 is provided inside the lower case 6, the protective sheet 13 is less likely to unnecessarily expand to adhere to the substrate 1.

[0040] A first decompression unit 16a is connected to the bottom wall or the side wall of the lower case 6. The first decompression unit 16a has a decompression passage 18a connected at one end to the lower case 6 and at the other end to a suction source 20a. Further, a switching valve 22a that switches between a communication state and a cutoff state of the decompression passage 18a is provided in the decompression passage 18a. In addition, a manometer 24a that can measure the air pressure of the space inside the lower case 6 is connected to the decompression passage 18a or the lower case 6.

[0041] In addition, a second decompression unit 16b is connected to the ceiling or the side wall of the upper case 8. The second decompression unit 16b has a decompression passage 18b connected at one end to the upper case 8 and at the other end to a suction source 20b. Further, a switching valve 22b that switches between a communication state and a cutoff state of the decompression passage 18b is provided in the decompression passage 18b. In addition, a manometer 24b that can measure the air pressure of the space inside the upper case 8 is connected to the decompression passage 18b or the upper case 8.

[0042] Further, a first atmosphere opening unit 26a is connected to a bottom wall or a side wall of the lower case 6. The first atmosphere opening unit 26a has a gas supply path 28a connected at one end to the lower case 6 and at the other end to the atmosphere outside the decompression chamber 4. Further, a switching valve 30a that switches between a communication state and a cutoff state of the gas supply path 28a is provided on the gas supply path 28a.

[0043] Further, a second atmosphere opening unit 26b is connected to a ceiling or a side wall of the upper case 8. The second atmosphere opening unit 26b has a gas supply path 28b connected at one end to the upper case 8 and at the other end to the atmosphere outside the decompression chamber 4. Further, a switching valve 30b that switches between a communication state and a cutoff state of the gas supply path 28b is provided on the gas supply path 28b.

[0044] Next, a protective sheet 13 provided to the front surface la of the substrate 1 will be described. The protective sheet 13 is a sheet that does not have a paste layer. Conventionally, a protective tape having a paste layer that protects the front surface la is attached to the front surface la of the substrate 1 that is processed by a processing device such as a grinding device. However, when the protective tape is attached to the front surface la of the substrate 1 that has a protrusion such as a bump provided to the front surface la, a part of the paste layer sometimes remains on the front surface la as a residue when the processing of the substrate 1 is completed and the protective tape is peeled off.

[0045] Therefore, in the protective sheet providing device and the method of providing a protective sheet of the present embodiment, the protective sheet 13 that does not have a paste layer is provided to the front surface la of the substrate 1 instead of the protective tape having a paste layer. The protective sheet 13 does not have a paste layer, and therefore a residue of a paste layer does not remain on the substrate 1 after the protective sheet 13 is peeled off.

[0046] The protective sheet 13 is, for example, a resin sheet that contains polyolefin or polyester as a material. The polyolefin is a polymer synthesized using an olefin as a monomer, and is, for example, polyethylene, polypropylene, or polystyrene. The polyester is a polymer synthesized using a dicarboxylic acid (a compound having two carboxyl groups) and a diol (a compound having two hydroxyl groups) as monomers. For example, polyethylene terephthalate or polyethylene naphthalate.

[0047] The protective sheet 13 does not have a paste layer, and therefore the protective sheet 13 cannot be directly provided to the front surface la of the substrate 1, and a substrate 1 with the protective sheet 13 cannot be formed. However, when the protective sheet 13 is heated to a temperature near the melting point to soften the protective sheet 13 and the protective sheet 13 is brought into contact with the front surface la of the substrate 1, the protective sheet 13 can be made to adhere to the front surface la, and the protective sheet 13 can be fixed to the substrate 1 to be provided.

[0048] A heating unit 14 that heats one or both of the protective sheet 13 or the substrate 1 is provided inside the reduced-pressure chamber 4 of the protective sheet attachment device 2. The heating unit 14 is provided, for example, inside the lower housing 6 of the support table 10 close to the support surface 10a, and has a heat source such as an electric heating wire. Alternatively, the heating unit 14 can be a heating gun that can deliver hot air, and can be provided to the inner wall of the lower housing 6 or the upper housing 8. Further, the heating unit 14 can be an infrared lamp that can irradiate infrared rays to the protective sheet 13 or the like.

[0049] In attaching the protective sheet 13 to the substrate 1 using the protective sheet attachment device 2, the lower housing 6 and the upper housing 8 of the reduced-pressure chamber 4 of the protective sheet attachment device 2 sandwich the protective sheet 13, and the space inside the reduced-pressure chamber 4 is partitioned by the protective sheet 13. Therefore, the protective sheet 13 is made to be the size that seals the opening 6a of the lower housing 6 and the opening 8a of the upper housing 8. For example, the diameter of the protective sheet 13 is made to be larger than the inner diameter of the protective sheet support portion 12. Alternatively, the diameter of the protective sheet 13 is made to be larger than the openings 6a and 8a.

[0050] Here, when the protective sheet 13 is firmly attached to the front surface la of the substrate 1, there is a problem that the protrusions 7 attached to the front surface la of the substrate 1 are peeled off from the substrate 1 together with the protective sheet 13 when the protective sheet 13 is peeled off from the substrate 1. On the other hand, when the adhesion of the protective sheet 13 to the front surface la of the substrate 1 is weak, there is a problem that the grinding water supplied to the substrate 1 or the like during grinding of the substrate 1 or the machining chips generated from the substrate or the like enter between the protective sheet 13 and the substrate 1.

[0051] Therefore, in order to not cause these problems, it is desirable to control the adhesion of the protective sheet 13 to the substrate 1. As described below, in the protective sheet attachment device and the method of attaching a protective sheet of the present embodiment, the protective sheet 13 can be attached to the substrate 1 at a desired strength that is controlled, and therefore these problems do not occur.

[0052] Next, the method of attaching a protective sheet of the present embodiment in which the protective sheet 13 is attached to the front surface la of the substrate 1 using the protective sheet attachment device 2 will be described. Figure 6 is a flowchart that describes the flow of each step of the method of attaching a protective sheet of the present embodiment.

[0053] In the method of attaching a protective sheet of the present embodiment, first, a substrate placement step S10 of placing the substrate 1 on the support table 10 is performed. Figure 2(B) is a cross-sectional view schematically showing the substrate placement step S10. In the substrate placement step S10, the substrate 1 is placed on the support surface 10a of the support table 10 in a state where the lower housing 6 and the upper housing 8 of the reduced-pressure chamber 4 are separated. At this time, the front surface la side of the substrate 1 is directed upward, and the back surface lb side is directed toward the support surface 10a of the support table 10.

[0054] In addition, the height of the support table 10 can be adjusted in advance so that the height position of the front surface la of the substrate 1 is below the height position of the upper end of the lower housing 6 when the substrate 1 is placed on the support surface 10a of the support table 10. However, the method of disposing the protective sheet of the present embodiment is not limited thereto, and the height position of the front surface la of the substrate 1 can also exceed the height position of the upper end of the lower housing 6 when the substrate 1 is placed on the support surface 10a of the support table 10.

[0055] After the substrate placement step S10 is performed, the space separation step S20 is performed to separate the space inside the reduced-pressure chamber 4 with the protective sheet 13 sandwiched by the lower housing 6 and the upper housing 8. Figure 3 (A) is a cross-sectional view schematically showing the space separation step S20. In the space separation step S20, first, the protective sheet 13 is placed on the substrate 1 and the lower housing 6 so as to face the front surface la of the substrate 1 placed on the support table 10 in a manner to close the opening 6a of the lower housing 6 with the protective sheet 13.

[0056] At this time, the protective sheet 13 is supported to the protective sheet support portion 12 in a region outside the front surface la of the substrate 1 and inside the opening 6a. Therefore, the protective sheet 13 is not easily lowered into the space inside the lower housing 6, and is not easily brought into contact with the side surface lc of the substrate 1. Therefore, when the protective sheet 13 is disposed to the substrate 1, it is possible to prevent the protective sheet 13 from unnecessarily expanding to adhere to the substrate 1.

[0057] Also, in the space separation step S20, next, the lower housing 6 and the upper housing 8 are brought close to each other, the protective sheet 13 is sandwiched by the lower housing 6 and the upper housing 8, and the lower housing 6 and the upper housing 8 are integrated. Thus, the space inside the reduced-pressure chamber 4 is separated into the first chamber 6b enclosed by the lower housing 6 and the protective sheet 13, and the second chamber 8b enclosed by the upper housing 8 and the protective sheet 13.

[0058] After the space separation step S20 is performed, the reduced pressure step S30 is performed. In the reduced pressure step S30, the first chamber 6b is reduced in pressure to a prescribed air pressure by the first reduced pressure unit 16a, and the second chamber 8b is reduced in pressure by the second reduced pressure unit 16b. When the first chamber 6b is reduced in pressure, the switching valve 22a is actuated to connect the suction source 20a to the first chamber 6b by the air supply path 28a. Also, when the second chamber 8b is reduced in pressure, the switching valve 22b is actuated to connect the suction source 20b to the second chamber 8b by the air supply path 28b.

[0059] Here, when the first chamber 6b and the second chamber 8b are reduced in pressure, the air pressure of the first chamber 6b is monitored by the air pressure gauge 24a, and the air pressure of the second chamber 8b is monitored by the air pressure gauge 24b. Also, the air pressure of the first chamber 6b is made to be a prescribed air pressure, and the air pressure of the second chamber 8b is made to be an air pressure corresponding to the prescribed air pressure.

[0060] At this time, the air pressure of the first chamber 6b can be substantially the same as the air pressure of the second chamber 8b, or lower than the air pressure of the second chamber 8b. When the air pressure of the first chamber 6b is significantly higher than the air pressure of the second chamber 8b, the protective sheet 13 can expand toward the second chamber 8b and peel from the front face la of the substrate 1.

[0061] After the reduced pressure step S30 is performed, the protective sheet close contact step S50 is performed, and the reduced pressure second chamber 8b is opened to the atmosphere by the second atmosphere opening unit 26b, so that the protective sheet 13 is caused to close contact to the substrate 1 in a manner that follows the unevenness of the front face la of the substrate 1. Figure 4 FIG. 10 is a cross-sectional view schematically showing the protective sheet close contact step S50.

[0062] In the protective sheet close contact step S50, the switching valve 22b of the second reduced pressure unit 16b is controlled to cut off the reduced pressure path 18b. Also, the switching valve 30b of the second atmosphere opening unit 26b is controlled to connect the second chamber 8b to the atmosphere outside of the reduced pressure chamber 4, and the air pressure of the second chamber 8b is returned to the atmospheric pressure. At this time, the more rapidly the air pressure of the second chamber 8b rises, the more uniformly the protective sheet 13 can be caused to close contact to the front face la of the substrate 1.

[0063] In addition, the strength of the close contact force of the protective sheet 13 to the front face la of the substrate 1 is influenced by the difference between the air pressure of the second chamber 8b (atmospheric pressure) that is raised to the atmospheric pressure in the protective sheet close contact step S50 and the air pressure of the first chamber 6b that is reduced in pressure by the first reduced pressure unit 16a. That is, the air pressure of the second chamber 8b is one of the elements that determine the strength of the close contact force of the protective sheet 13.

[0064] Therefore, in the protective sheet arrangement method of the present embodiment, the air pressure of the second chamber 8b in which the pressure reduction is performed in the pressure reduction step S30 is controlled to a prescribed air pressure so that the adhesion of the protective sheet 13 to the substrate 1 becomes an appropriate strength. By making the second chamber 8b a prescribed air pressure, the strength of the adhesion of the protective sheet 13 to the substrate 1 is made a prescribed degree. That is, by controlling the air pressure of the second chamber 8b, the adhesion of the protective sheet 13 can be controlled.

[0065] The prescribed air pressure is set, for example, so that the adhesion of the protective sheet 13 to the substrate 1 becomes a strength that is a degree that the bump 7 does not peel off from the front surface la together with the protective sheet 13 when the protective sheet 13 is peeled off from the substrate 1. In addition, the prescribed air pressure is set, for example, so that the adhesion of the protective sheet 13 to the substrate 1 becomes a strength that is a degree that a gap does not occur between the substrate 1 and the protective sheet 13 when the substrate 1 is processed so that processing chips or processing water do not enter the gap.

[0066] Figure 5 (A) and Figure 5 (B) of FIG. 10 are cross-sectional views that schematically show the protective sheet 13 arranged on the front surface la of the substrate 1 enlarged. In Figure 5 (A) of FIG. 10 schematically shows a case where the protective sheet 13 is arranged on the front surface la of the substrate 1 with a relatively strong adhesion, and in Figure 5 (B) of FIG. 10 schematically shows a case where the protective sheet 13 is arranged on the front surface la of the substrate 1 with a relatively weak adhesion.

[0067] The appropriate strength of the adhesion of the protective sheet 13 to the substrate 1 is influenced by various factors such as the shape of the concavo-convex formed on the front surface la of the substrate 1, the physical properties of the components exposed on the front surface la, the physical properties of the protective sheet 13, the thickness or hardness of the substrate 1 and the protective sheet 13, and the like. Therefore, the substrate 1 and the protective sheet 13 can be prepared, an experiment of making the pressure of the first chamber 6b vary in various ways to make the protective sheet 13 adhere to the substrate 1 and test the adhesion can be performed, and the air pressure of the first chamber 6b that can provide the most appropriate adhesion can be explored in advance.

[0068] In the protective sheet arrangement device and the protective sheet arrangement method of the present embodiment, by making the air pressure of the first chamber 6b a prescribed air pressure in the pressure reduction step S30, the protective sheet 13 can be arranged on the substrate 1 with an adhesion of a prescribed strength. That is, the air pressure of the first chamber 6b is controlled so as to control the adhesion of the protective sheet 13 to the substrate 1, and the protective sheet 13 is appropriately arranged on the substrate 1.

[0069] Further, after the spatial separation step S20 and before the substrate unloading step S60 described later, a heating step S40 of heating one or both of the protective sheet 13 and the substrate 1 is performed. In the heating step S40, the protective sheet 13 and the substrate 1 are heated, for example, in a state where the protective sheet 13 is in contact with the front surface la of the substrate 1, by causing the heating unit 14 to operate, so as to soften the protective sheet 13. Here, the heating temperature of the substrate 1 and the protective sheet 13 can be a temperature in the vicinity of the melting point of the protective sheet 13.

[0070] In the protective sheet attaching apparatus and the method of attaching a protective sheet according to the present embodiment, the protective sheet 13 is pressed against the front surface la of the substrate 1 with a prescribed force in a state where the protective sheet 13 is heated to a prescribed temperature, so as to cause the protective sheet 13 to adhere to the front surface la of the substrate 1. Alternatively, the protective sheet 13 is heated to a prescribed temperature in a state where the protective sheet 13 is pressed against the front surface la of the substrate 1 with a prescribed force, so as to cause the protective sheet 13 to adhere to the front surface la of the substrate 1.

[0071] Alternatively, the substrate 1 can be heated in a state where the substrate 1 and the protective sheet 13 are separated, the protective sheet 13 can be brought into contact with the substrate 1 and pressed with a prescribed force, and the protective sheet 13 can be heated to a prescribed temperature by transferring heat from the substrate 1 to the protective sheet 13.

[0072] Further, it is preferable that the heating step S40 be performed after the spatial separation step S20 and before the protective sheet adhering step S50. It is more preferable that the heating step S40 be performed after the pressure reduction step S30 and before the protective sheet adhering step S50.

[0073] In the method of attaching a protective sheet according to the present embodiment, after the protective sheet adhering step S50, a substrate unloading step S60 is performed. Figure 4 FIG. 8 is a cross-sectional view schematically showing the substrate unloading step S60. In the substrate unloading step S60, the first chamber 6b that has been under reduced pressure is opened to the atmosphere by the first atmosphere opening unit 26a, the lower housing 6 and the upper housing 8 are separated, and the substrate 1 to which the protective sheet 13 adheres is unloaded from the reduced-pressure chamber 4.

[0074] When the first chamber 6b is opened to the atmosphere by the first atmosphere opening unit 26a, the switching valve 22a of the first pressure reduction unit 16a is caused to operate to shut off the reduced-pressure path 18a. Also, the switching valve 30a of the first atmosphere opening unit 26a is caused to operate to connect the first chamber 6b to the atmosphere outside the reduced-pressure chamber 4, and the air pressure of the first chamber 6b is returned to the atmospheric pressure. As a result, both the first chamber 6b and the second chamber 8b become the atmospheric pressure, so the lower housing 6 and the upper housing 8 can be separated.

[0075] When the lower case 6 and the upper case 8 are separated, the substrate 1 with the protective sheet 13 can be carried out from the reduced-pressure chamber 4. Then, a remaining area cutting step can be performed, and a portion of the side surface lc of the substrate 1 outside the protective sheet 13 is cut off by a cutter or the like cutting unit. In addition, a processing step can be performed thereafter, and the back surface lb of the substrate 1 provided with the protective sheet 13 on the front surface la is processed by grinding or the like. In addition, a peeling step can be performed thereafter, and the protective sheet 13 is peeled from the front surface la of the processed substrate 1.

[0076] According to the protective sheet providing device and the protective sheet providing method of the present embodiment, the protective sheet 13 can be provided on the front surface la of the substrate 1 with a controlled close contact force. Therefore, the close contact force can be controlled so that the bump 7 formed on the front surface la does not peel off or the like when the protective sheet 13 is peeled from the substrate 1.

[0077] In addition, the present application is not limited to the description of the above-described embodiments, and various modifications and implementations can be made. For example, in the above-described embodiments, a case in which the protective sheet 13 is provided on the front surface la of the substrate 1 provided with a concavo-convex on the front surface la side is described, but the protective sheet providing device and the protective sheet providing method of one embodiment of the present application are not limited thereto.

[0078] That is, the protective sheet 13 can also be provided on the back surface lb of the substrate 1. In addition, the concavo-convex such as the bump 7 can not be provided on the front surface la to which the protective sheet 13 is provided, and the device 5 can not be provided.

[0079] In addition to the above, the configuration, method, and the like of the above-described embodiments and modified examples can be appropriately changed and implemented as long as they do not deviate from the scope of the object of the present application.

Claims

1. A protective sheet mounting device, which mounts a protective sheet onto the front side of a substrate having irregularities on its front side, characterized in that, The protective plate is equipped with the following features: The decompression chamber can be separated into an upper shell and a lower shell; A support worktable, which is disposed inside the lower housing, is used to place the substrate; The first pressure relief unit is connected to the lower housing. The first atmospheric open unit is connected to the lower shell; The second pressure relief unit is connected to the upper housing; and The second atmospheric open unit is connected to the upper shell. The first pressure reduction unit is capable of reducing the pressure of the first chamber within the pressure reduction chamber to a specified pressure. The first chamber is formed by a protective plate disposed on the base plate placed on the support worktable and sandwiched between the upper housing and the lower housing. The second decompression unit is capable of decompressing the second chamber within the decompression chamber. The second chamber is formed by a protective plate disposed on the base plate placed on the support worktable and sandwiched between the upper housing and the lower housing, and the upper housing. The second atmospheric opening unit allows atmospheric pressure to act directly on the entire surface of the protective sheet by opening the depressurized second chamber to the atmosphere, thereby ensuring that the protective sheet is firmly attached to the front surface of the substrate with a specified strength. The first atmospheric opening unit opens the first chamber to the atmosphere after opening the second chamber to the atmosphere using the second atmospheric opening unit, thereby enabling the upper housing of the decompression chamber to be separated from the lower housing, and the substrate attached to the protective sheet to be removed from the decompression chamber.

2. The protective sheet mounting device according to claim 1, characterized in that, The protective sheet mounting device has a protective sheet support portion that supports the protective sheet disposed on the substrate mounted on the support worktable around the support worktable.

3. The protective sheet mounting device according to claim 1 or 2, characterized in that, The protective sheet mounting device has a heating unit that heats one or both of the protective sheet and the substrate.

4. A method for dispensing a protective sheet, wherein a protective sheet is disposed on the front side of a substrate having irregularities on the front side, characterized in that, The installation method of this protective plate has the following steps: In the substrate placement step, with the lower housing and the upper housing of the decompression chamber, which can be separated into an upper housing and a lower housing, separated, the substrate is placed on a support worktable with the front side facing upward. The decompression chamber includes the support worktable disposed inside the lower housing for placing the substrate, a first decompression unit and a first atmosphere opening unit both connected to the lower housing, and a second decompression unit and a second atmosphere opening unit both connected to the upper housing. In the spatial separation step, the protective sheet is placed on the substrate and the lower housing, facing the front side of the substrate placed on the support worktable. The lower housing and the upper housing are used to clamp the protective sheet and integrate the lower housing and the upper housing, thereby separating the space inside the decompression chamber into a first chamber enclosed by the lower housing and the protective sheet and a second chamber enclosed by the upper housing and the protective sheet. The decompression step involves decompressing the first chamber to a specified pressure using the first decompression unit, and decompressing the second chamber using the second decompression unit. In the protective sheet bonding step, the second atmospheric opening unit opens the depressurized second chamber to the atmosphere, allowing atmospheric pressure to directly act on the entire surface of the protective sheet. This causes the protective sheet to adhere tightly to the substrate with a predetermined strength, mimicking the unevenness of the front side of the substrate; and In the substrate removal step, after the protective sheet is attached, the first atmospheric opening unit is used to open the first chamber after depressurization to the atmosphere, the lower housing and the upper housing are separated, and the substrate with the protective sheet attached is removed from the depressurization chamber.

5. The method for configuring the protective sheet according to claim 4, characterized in that, The protective sheet is a resin sheet containing polyolefins or polyesters.

6. The method for arranging the protective sheet according to claim 4 or 5, characterized in that, The method for installing the protective sheet also includes the following heating step: after the space separation step and before the substrate removal step, one or both of the protective sheet and the substrate are heated.

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