Method for processing plate-like object

Abstract

To provide a method for processing a plate-like object capable of efficiently peeling a protective member from the plate-like object.SOLUTION: A method for processing a plate-shaped object includes: a fixing step 101 of fixing a protective member to one surface of the plate-shaped object before a cleaning step; a processing step 102 of processing the other surface of the plate-shaped object; a cleaning step 103 of cleaning the plate-shaped object in a cleaning unit having a cleaning table and a nozzle that supplies a cleaning liquid to the plate-shaped object held on the cleaning table before a first peeling step 104; the first peeling step 104 of peeling the protective member from an outer peripheral portion of the plate-shaped object by causing a fluid to enter between the plate-shaped object and the protective member fixed to one surface of the plate-shaped object; and a second peeling step 105 of peeling the entire surface of the protective member from the plate-shaped object with a portion from which the protective member is peeled in the first peeling step 104 as a starting point.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for processing a plate-like object.

Background Art

[0002] In order to planarize one surface of a wafer which is a plate-like object, a method has been proposed in which the other surface is covered with a protective member made of resin and grinding or the like is performed on one surface (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the method disclosed in Patent Document 1 and the like, when peeling the protective member from the plate-like object, conventionally, the outer edge of the protective member covering the plate-like object was nipped and peeled by moving relative to the plate-like object. For this reason, there has been a problem that the load applied to the plate-like object is large, it takes time to peel off gradually at a low speed, and the working efficiency is reduced.

[0005] An object of the present invention is to provide a method for processing a plate-like object capable of efficiently peeling a protective member from the plate-like object.

Means for Solving the Problems

[0006] In order to solve the above-described problems and achieve the object, the method for processing a plate-like object of the present invention includes a first peeling step of allowing a fluid to penetrate between the plate-like object and a protective member fixed to one surface of the plate-like object, and peeling the protective member from at least a part of the outer peripheral portion of the plate-like object, and a second peeling step of peeling the entire surface of the protective member from the plate-like object starting from the portion where the protective member has peeled off in the first peeling step.

[0007] In the method for processing the plate-like object, the protective member has a protruding portion that slightly protrudes from the outer edge of the plate-like object, and in the first peeling step, fluid may be supplied to the protruding portion.

[0008] In the method for processing the plate-like object, before the first peeling step, in a cleaning unit having a cleaning table and a nozzle for supplying a cleaning liquid to the plate-like object held on the cleaning table, a cleaning step of cleaning the plate-like object is provided, and the first peeling step may be carried out with the plate-like object held on the cleaning table.

[0009] In the method for processing the plate-like object, before the cleaning step, a fixing step of fixing the protective member to one surface of the plate-like object and a processing step of processing the other surface of the plate-like object may be provided.

[0010] In the method for processing the plate-like object, in the processing step, the plate-like object may be ground with a grinding wheel.

Advantages of the Invention

[0011] The present invention has the effect of being able to efficiently peel the protective member from the plate-like object.

Brief Description of the Drawings

[0012]

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DETAILED DESCRIPTION OF THE INVENTION

[0013] The embodiments for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the content described in the following embodiments. In addition, the constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Also, various omissions, substitutions, or changes in the configuration can be made without departing from the gist of the present invention.

[0014] 〔Embodiment 1〕 The method for processing a plate-like object according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing a configuration example of the plate-like object to be processed in the method for processing a plate-like object according to Embodiment 1. FIG. 2 is a flowchart showing the flow of the method for processing a plate-like object according to Embodiment 1.

[0015] (Plate-like object) The method for processing a plate-like object according to Embodiment 1 is a processing method for the plate-like object 1 shown in FIG. 1. In Embodiment 1, the plate-like object 1 to be processed in the method for processing a plate-like object is a substrate made of silicon, sapphire, gallium arsenide, or SiC (silicon carbide), etc., and constitutes a disc-shaped semiconductor wafer, an optical device wafer, etc.

[0016] The plate-like object 1 is an as-sliced wafer obtained by slicing (cutting) a columnar ingot into a disc shape with a wire saw, and is before a device is formed. The plate-like object 1 has undulations and warps formed on one surface 2 during cutting with a wire saw or the like. After forming a protective member 10 (shown in FIG. 5) by applying a liquid resin 5 (shown in FIG. 3) to one surface 2 of the plate-like object 1, the other surface 3 and one surface 2 of the plate-like object 1 are sequentially ground to be flattened.

[0017] The method for processing a plate-like object according to Embodiment 1 is a method for flattening the other surface 3 of the plate-like object 1. The method for processing a plate-like object according to Embodiment 1 includes a fixing step 101, a processing step 102, a cleaning step 103, a first peeling step 104, and a second peeling step 105, as shown in FIG. 2.

[0018] (Fixing step) FIG. 3 is a side view schematically showing in a partial cross-section a state in which a liquid resin is supplied to a sheet on a stage in the fixing step of the method for processing a plate-like object shown in FIG. 2. FIG. 4 is a side view schematically showing in a partial cross-section a state in which one surface of the plate-like object is pressed against the liquid resin shown in FIG. 3. FIG. 5 is a side view schematically showing in a partial cross-section a state in which the liquid resin shown in FIG. 4 is cured.

[0019] The fixing step 101 is a step of fixing the protective member 10 to one surface 2 of the plate-like object 1 before the cleaning step 103. In Embodiment 1, in the fixing step 101, as shown in FIG. 3, the fixing device 20 places the disc-shaped sheet 4 on the flat upper surface 23 of the glass table 22 of the stage 21. The sheet 4 prevents the liquid resin 5 from being dropped directly onto the upper surface 23 of the glass table 22 of the stage 21, protects the upper surface 23 of the glass table 22 of the stage 21 from being scratched, and prevents the trouble of cleaning. In Embodiment 1, the sheet 4 is made of a resin having flexibility and is formed with a constant thickness, and is formed with an outer diameter larger than the outer diameter of the plate-like object 1. The sheet 4 is composed of, for example, polyolefin. Note that the sheet 4 may have the same diameter as the plate-like object 1 or be slightly smaller.

[0020] In Embodiment 1, in the fixing step 101, as shown in FIG. 3, the fixing device 20 supplies the liquid resin 5 from the supply nozzle 24 onto the center of the sheet 4. The liquid resin 5 is composed of, for example, an ultraviolet curable resin that cures when irradiated with ultraviolet rays. In Embodiment 1, in the fixing step 101, as shown in FIG. 4, the fixing device 20 sucks and holds the other surface 3 of the plate-like object 1 on the lower surface 26 of the transfer unit 25, positions the plate-like object 1 and the sheet 4 coaxially, and then presses one surface 2 of the plate-like object 1 sucked and held by the transfer unit 25 against the liquid resin 5 on the sheet 4.

[0021] In Embodiment 1, in the fixing step 101, the fixing device 20 presses the plate-like object 1 sucked and held by the transfer unit 25 against the liquid resin 5 on the sheet 4, expands the liquid resin 5 in the radial direction of the plate-like object 1, and covers the entire one surface 2 of the plate-like object 1 with the liquid resin 5. In Embodiment 1, in the fixing step 101, as shown in FIG. 5, the fixing device 20 turns on the ultraviolet lamp 27 in the glass table 22, irradiates the liquid resin 5 with ultraviolet rays 28, cures the liquid resin 5, and fixes the protective member 10 composed of the sheet 4 and the cured resin 5 to the entire one surface 2 of the plate-like object 1.

[0022] In Embodiment 1, since the sheet 4 has a larger diameter than the plate-like object 1, the protective member 10 has a protruding portion 11 that slightly protrudes from the outer edge of the plate-like object 1. In the embodiment, the protruding portion 11 is composed of the sheet 4 or the resin 5 that protrudes from the outer edge of the sheet 4 and the plate-like object 1 and has hardened.

[0023] (Processing Step) FIG. 6 is a side view schematically showing, in partial cross-section, the processing steps of the method for processing the plate-like object shown in FIG. 2. Processing step 102 is a step of processing and flattening the other surface 3 of the plate-like object 1. In Embodiment 1, in processing step 102, the grinding device 30 sucks and holds the one surface 2 side of the plate-like object 1 via the protective member 10 on the holding surface 32 of the holding table 31.

[0024] In Embodiment 1, in processing step 102, as shown in FIG. 6, the grinding device 30 rotates the grinding wheel 34 of the grinding unit 33 around an axis parallel to the vertical direction while rotating the holding table 31 around an axis parallel to the vertical direction, and brings the grinding wheel 35 of the grinding wheel 34 into contact with the other surface 3 of the plate-like object 1, and feeds the grinding unit 33 toward the other surface 3 of the plate-like object 1 to grind the other surface 3 with the grinding wheel 35.

[0025] In Embodiment 1, in processing step 102, the grinding device 30 thins the plate-like object 1 to a predetermined thickness 8, and when the plate-like object 1 is thinned to the predetermined thickness, the grinding unit 33 is raised. Thus, in Embodiment 1, in processing step 102, the other surface 3 of the plate-like object 1 is ground with the grinding wheel 34, which is a processing operation, to flatten the other surface 3. However, in the present invention, in processing step 102, the other surface 3 of the plate-like object 1 may be flattened by performing grinding and polishing operations, or by performing grinding, polishing, and etching operations.

[0026] (Washing Step) FIG. 7 is a side view schematically showing in partial cross-section the cleaning step of the method for processing the plate-like object shown in FIG. 2. The cleaning step 103 is a step of cleaning the plate-like object 1 in a cleaning device 40 which is a cleaning unit having a cleaning table 41 and a nozzle 43 for supplying a cleaning liquid 44 to the plate-like object 1 held on the cleaning table 41, before the first peeling step 104.

[0027] In Embodiment 1, in the cleaning step 103, the cleaning device 40 sucks and holds the one surface 2 side of the plate-like object 1 on the holding surface 42 of a disc-shaped cleaning table 41 having a smaller diameter than the plate-like object 1 via a protection member 10, and exposes the outer edge portion of the plate-like object 1 from the holding surface 42. In Embodiment 1, in the cleaning step 103, the cleaning device 40 positions the plate-like object 1 at a position coaxial with the holding surface 42 of the cleaning table 41.

[0028] In Embodiment 1, in the cleaning step 103, as shown in FIG. 7, the cleaning device 40 rotates the cleaning table 41 around its axis and supplies the cleaning liquid 44 (pure water in the embodiment) from the nozzle 43 above the center of the cleaning table 41 onto the center of the other surface 3 of the plate-like object 1. Then, the cleaning liquid 44 flows toward the outer periphery of the plate-like object 1 due to the centrifugal force of the rotation of the cleaning table 41, washes away the entire other surface 3 of the plate-like object 1, and cleans it.

[0029] (First Peeling Step) FIG. 8 is a side view schematically showing in partial cross-section the first peeling step of the method for processing the plate-like object shown in FIG. 2. The first peeling step 104 is a step of allowing a cleaning liquid 44 which is a fluid to penetrate between the plate-like object 1 and a protection member 10 fixed to one surface 2 of the plate-like object 1, and peeling the protection member 10 from at least a part of the outer peripheral portion of the plate-like object 1.

[0030] In Embodiment 1, in the first peeling step 104, the cleaning device 40 positions the nozzle 43 above the protruding portion 11 of the protection member 10 fixed to the plate-like object 1 suction-held on the cleaning table 41, and as shown in FIG. 8, while rotating the cleaning table 41 around the axis, the cleaning liquid 44 is supplied from the nozzle 54 to the protruding portion 11. Then, the cleaning liquid 44 supplied to the protruding portion 11 presses the protruding portion 11 downward to peel the outer edge portion of the protection member 10 from the outer peripheral portion of the plate-like object 1 and enter between one surface 2 of the plate-like object 1 and the protection member 10. Thus, the first peeling step 104 is carried out with the plate-like object 1 held on the cleaning table 41. Also, in Embodiment 1, in the first peeling step 104, the cleaning table 41 is rotated to peel the outer edge portion of the protection member 10 from the outer peripheral portion of the plate-like object 1 over the entire circumference, but in the present invention, a part of the outer edge portion of the protection member 10 may remain fixed to the outer peripheral portion of the plate-like object 1.

[0031] (Second peeling step) FIG. 9 is a side view schematically showing in partial cross section a state in which the outer edge portion of the protection member is clamped by the clamping member in the second peeling step of the method for processing the plate-like object shown in FIG. 2. FIG. 10 is a side view schematically showing in partial cross section a state in which the protection member is peeled by the clamping member in the second peeling step of the method for processing the plate-like object shown in FIG. 2.

[0032] The second peeling step 105 is a step of peeling the entire surface of the protection member 10 from the plate-like object 1 starting from a part of the outer edge portion which is the portion where the protection member 10 was peeled in the first peeling step 104. In Embodiment 1, in the second peeling step 105, the peeling device 50 suction-holds the other surface 3 of the plate-like object 1 on the lower surface 52 of the holding unit 51.

[0033] In Embodiment 1, in the second peeling step 105, as shown in FIG. 9, the peeling device 50 clamps a part of the outer edge of the protective member 10 peeled from the outer peripheral part of the plate-like object 1 by the clamping member 53. In Embodiment 1, in the second peeling step 105, as shown in FIG. 10, the peeling device 50 moves the clamping member 53 along one surface 2 of the plate-like object 1 toward the center of the plate-like object 1, and moves the clamping member 53 through the lower part of the center of the plate-like object 1 toward the outer edge of the plate-like object 1 to peel the protective member 10, that is, the cured liquid resin 5 and the sheet 4, from one surface 2 of the plate-like object 1.

[0034] As described above, in the method for processing a plate-like object according to Embodiment 1, in the first peeling step 104, the cleaning liquid 44 is allowed to penetrate between the plate-like object 1 and the protective member 10 fixed to one surface 2 of the plate-like object 1, and the protective member 10 is peeled from the outer peripheral part of the plate-like object 1. Therefore, in the second peeling step 105, the protective member 10 can be smoothly peeled from the plate-like object 1 in order from the peeled outer edge of the protective member 10.

[0035] As a result, the method for processing a plate-like object according to Embodiment 1 has the effect that the peeling time can be reduced and the protective member 10 can be efficiently peeled from the plate-like object 1.

[0036] In Embodiment 1, the cleaning liquid 44 as a fluid is supplied from the nozzle 43 in the first peeling step 104. However, in the present invention, the fluid may be supplied from a nozzle different from the nozzle 43 for cleaning the plate-like object 1. Further, in the present invention, the fluid may be pure water, air, a two-fluid of pure water and air, high-pressure water, or the cleaning liquid 44 containing a surfactant.

[0037] In the present invention, as shown in FIG. 11, the protective member 10 may have the same diameter as the plate-like object 1 or may be slightly smaller without including the protruding portion 11. In this case, in the first peeling step 104, as shown in FIG. 11, it is desirable to inject the fluid 46 from the cleaning table 41 and the nozzle 45 positioned on the outer peripheral side of the plate-like object 1 along the radial direction of the plate-like object 1 toward the space between the protective member 10 and one surface 2 of the plate-like object 1. Note that FIG. 11 is a side view schematically showing a partial cross section of a modified example of the first peeling step shown in FIG. 8. In FIG. 11, the same reference numerals are given to the same parts as those in Embodiment 1, and the description thereof is omitted.

[0038] Note that the present invention is not limited to the above-described embodiment. That is, various modifications can be made without departing from the gist of the present invention.

Explanation of Reference Numerals

[0039] 1 Plate-like object 2 One surface 3 The other surface 10 Protective member 11 Protruding portion 34 Grinding wheel 40 Cleaning device (cleaning unit) 41 Cleaning table 43 Nozzle 44 Cleaning liquid (fluid) 46 Fluid 101 Fixing step 102 Processing step 103 Cleaning step 104 First peeling step 105 Second peeling step

Claims

1. A first peeling step of allowing a fluid to penetrate between a plate-like object and a protective member fixed to one surface of the plate-like object, and peeling the protective member from at least a part of the outer peripheral portion of the plate-like object; A second peeling step of peeling the entire surface of the protective member from the plate-like object starting from the portion where the protective member has peeled in the first peeling step. A method for processing a plate-like object, comprising:

2. The protective member has a protruding portion that slightly protrudes from the outer edge of the plate-like object. The method for processing a plate-like object according to claim 1, wherein in the first peeling step, a fluid is supplied to the protruding portion.

3. Before the first peeling step, in a cleaning unit having a cleaning table and a nozzle for supplying a cleaning liquid to the plate-like object held on the cleaning table, a cleaning step of cleaning the plate-like object. The method for processing a plate-like object according to claim 1, wherein the first peeling step is performed while the plate-like object is held on the cleaning table.

4. A fixing step of fixing the protective member to one surface of the plate-like object before the cleaning step; A processing step of processing the other surface of the plate-like object. The method for processing a plate-like object according to claim 3, comprising:

5. The processing step is characterized by grinding the plate-like object with a grinding wheel. The method for processing a plate-like object according to claim 4.

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