JP4316187B2 - Method and apparatus for peeling brittle material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a peeling method及beauty peeling apparatus brittle material, more particularly, to a method及beauty peeling apparatus to peel off the brittle material of the semiconductor wafer or the like which is attached to a rigid plate via the adhesive sheet.
[0002]
[Prior art]
Conventionally, semiconductor wafers having a circuit pattern formed on the surface have been widely used in the electronics industry, the optical industry, and the like. The thickness of this semiconductor wafer has been conventionally ground to about 200 μm to 300 μm, but due to the recent demand for miniaturization and thinning of IC chips, processing to ultra-thin of about 50 μm is becoming mainstream. . Therefore, when the semiconductor wafer after grinding is stored and transported, the semiconductor wafer is likely to be cracked or scratched. Therefore, there is a case where a method of fixing the semiconductor wafer to a hard plate such as a glass plate is used in order to reinforce the semiconductor wafer and ensure the handling property of the semiconductor wafer before grinding. When fixing a semiconductor wafer to a hard board, the method of sticking these through wax is known.
[0003]
[Problems to be solved by the invention]
However, when pasting through the wax, it is difficult to uniformly apply the thickness of the wax, and it becomes difficult to smooth and grind the semiconductor wafer. In addition, there is a strong tendency for the wax to protrude from the end portion of the hard wax plate, resulting in inconvenience that workability is hindered. Furthermore, after the semiconductor wafer is peeled off from the hard plate, it must be cleaned using an organic solvent, which is not preferable in that it causes pollution of the natural environment.
[0004]
Therefore, as disclosed in Japanese Patent Application Laid-Open No. 2000-136362, the present applicant uses a double-sided pressure-sensitive adhesive sheet having pressure-sensitive adhesive layers on both sides of a heat-shrinkable film instead of wax, and a hard plate and a semiconductor wafer. A method of pasting is proposed.
[0005]
However, when the sheet is attached using the sheet, there is a disadvantage that it cannot be used in a process having a heat treatment after the grinding process. In addition, since such a sheet is usually set to substantially the same plane size as the semiconductor wafer, it is difficult to create an opportunity to start peeling when the semiconductor wafer is peeled from the hard plate. For this reason, there is a problem that an excessive force is required in the initial stage of peeling, and the semiconductor wafer is damaged, or if it is carefully operated so as not to apply a force, peeling cannot be performed.
[0006]
OBJECT OF THE INVENTION
The present invention has been devised by paying attention to such inconveniences, and its purpose is to easily peel a brittle material such as a semiconductor wafer attached to a hard plate, and at the time of peeling. to provide a peeling method及beauty peeling apparatus brittle material which can prevent the occurrence of cracks and scratches brittle material.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is a method of peeling and fixing a brittle material having a first notch on the outer periphery while being fixed to a hard plate via a double-sided pressure-sensitive adhesive sheet.
The hard plate has a second cutout portion of the same shape in the first cutout portion on the outer periphery,
The double-sided pressure-sensitive adhesive sheet is disposed so that the first and second cutout portions face each other and are exposed to the respective cutout portions, and a brittle material is stuck and fixed to a hard plate through the first and second cutout portions. A technique is adopted in which stress is applied to the exposed portion of the double-sided pressure-sensitive adhesive sheet in the region of the first and second cutout portions to peel the brittle material. According to such a technique, the end of the brittle material can be peeled without applying excessive force, and the peeled portion is used as a trigger to peel off the brittle material and the double-sided pressure-sensitive adhesive sheet so as to gradually expand the peeled area. It is possible to reduce the load on the brittle material during peeling. Therefore, even a brittle material whose rigidity has been reduced due to ultrathinning can be easily peeled off from the hard plate, and cracking of the brittle material and the hard plate can be prevented. And since it can peel without using an organic solvent like the past, it can respond to a recent environmental problem.
[0008]
Moreover, in the said peeling method, when peeling the said brittle material, the method of interposing a peeling promotion means between a double-sided adhesive sheet and a brittle material can be taken. By such a technique, it is possible to further reduce the peeling resistance acting on the brittle material, and it is possible to smoothly peel off the peeling area between the brittle material and the double-sided pressure-sensitive adhesive sheet.
[0009]
Furthermore, the brittle material in the present invention can be targeted for semiconductor wafers. By applying the present invention to such a semiconductor wafer, it is possible to sufficiently meet demands for strict processing accuracy. In addition, since the semiconductor wafer is generally provided with a first notch such as a notch indicating the crystal orientation, the semiconductor wafer can be peeled off using a notch without special processing.
[0010]
Further, the present invention can be applied to a semiconductor wafer that has been processed to a thin thickness by grinding the release surface after the semiconductor wafer is stuck and fixed to the hard plate.
[0012]
Further, in the peeling device according to the present invention, the brittle material having the first notch on the outer periphery is a hard material having the second notch having the same shape in the first notch via the double-sided pressure-sensitive adhesive sheet. In a peeling device for peeling the brittle material from a unit that is stuck and fixed to a plate,
A fixed table for fixing the brittle material or hard plate side of the unit;
The first and second cutout portions are provided with stress applying means capable of applying stress to the double-sided pressure-sensitive adhesive sheet portion where the front and back surfaces are exposed.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 shows a schematic perspective view of a hard plate and a brittle material before being stuck through a sheet to which the method according to the present invention is applied, and FIG. 2 shows the hard plate and the ultrathin member. An enlarged cross-sectional view after pasting is shown. In these drawings, the brittle material 10 is affixed to the plane of the hard plate 11 (upper surface in FIG. 2) via a double-sided adhesive sheet 12.
[0015]
The brittle material 10 has a first cutout 14 on the outer periphery (right end side in FIG. 1). Examples of such brittle material 10 include semiconductor wafers and thin plates such as ceramics and glass. In particular, semiconductor wafers that are ground and have a thickness of about 100 μm or less are targeted. The semiconductor wafer usually has one V notch formed for positioning indicating the crystal orientation, and this V notch is used as the first notch portion 14.
[0016]
As the hard plate 11, for example, a plastic plate such as a glass plate, a quartz plate, an acrylic plate, a polyvinyl chloride plate, a polyethylene terephthalate plate, a polypropylene plate, or a polycarbonate plate can be used. The hardness defined by ASTM D 883 of the hard plate is preferably 70 MPa or more. The thickness of the hard plate is usually about 0.1 to 10 mm, although it depends on the material. Moreover, when using an ultraviolet curable adhesive for the adhesive layer of the double-sided pressure-sensitive adhesive sheet 12, the hard plate is formed of an ultraviolet light transmissive material.
The hard plate 11 is formed with a second notch 16 corresponding to the first notch 14 on the outer periphery (right end side in FIG. 1). The shape of the second cutout portion 16 is processed so as to be substantially the same shape as the first cutout portion 14.
[0017]
The double-sided pressure-sensitive adhesive sheet 12 used in the present invention is coated and formed on the base film 18, the pressure-sensitive adhesive layer 19 that is applied and formed on the side of the base film 18 that is applied to the brittle material 10, and the side that is applied to the hard plate 11. The pressure-sensitive adhesive layer 19 ′. Since the base film 18 is excellent in dimensional stability and heat resistance, a polyester film such as a polyethylene terephthalate film or a polyethylene naphthalate film is preferably used. The pressure-sensitive adhesive layers 19 and 19 ′ are not limited as long as they are re-peelable pressure-sensitive adhesives, but rubber-based, acrylic-based, silicone-based, polyurethane-based, polyvinyl ether-based re-peelable pressure-sensitive adhesives, An ultraviolet curable adhesive or a water-swellable adhesive is used.
Among the pressure-sensitive adhesive layers 19 and 19 ′, the pressure-sensitive adhesive layer provided on the adherend (brittle material 10 or hard plate 11) to be peeled first when performing a peeling operation is a UV-curable pressure-sensitive adhesive. It is particularly preferable that the composition consists of an agent. If the pressure-sensitive adhesive layer is a UV-curable pressure-sensitive adhesive and has been UV-cured before the peeling operation, even if the pressure-sensitive adhesive surface comes into contact with the adherend during the peeling operation, it does not stick again.
The pressure-sensitive adhesive layer provided on the opposite surface of the pressure-sensitive adhesive layer (side to be peeled later) can use the above-mentioned pressure-sensitive adhesive, and the pressure-sensitive adhesive layer provided on both sides may be the same type of pressure-sensitive adhesive, May be different.
[0018]
The brittle material 10 attached to the hard plate 11 via the double-sided pressure-sensitive adhesive sheet 12 is peeled off by, for example, a peeling device 21 shown in FIGS. The peeling device 21 includes a fixed table 22 provided so that the brittle material 10 can be placed and held, and a pin 23 capable of pressing the double-sided pressure-sensitive adhesive sheet 12 in the first and second cutout portions 14 and 16. And a nozzle 26 (see FIG. 4) capable of blowing out compressed air A as a peeling promoting means between the brittle material 10 and the double-sided pressure-sensitive adhesive sheet 12. The pin 23 and the nozzle 26 are supported by a robot arm or the like (not shown), and are provided so as to be relatively movable with respect to the vicinity of the position facing the notches 14 and 16 on the fixed table 22. In addition, each apparatus etc. which comprise the peeling apparatus 21 are controlled entirely via the control apparatus which is not shown in figure.
[0019]
In this way, by interposing the compressed air A between the brittle material 10 and the double-sided pressure-sensitive adhesive sheet 12, it can be easily peeled off so as to gradually expand the peeling region from around the pressing position of the double-sided pressure-sensitive adhesive sheet 12, In addition, it is possible to minimize the peeling resistance between the brittle material 10 and the double-sided pressure-sensitive adhesive sheet 12. Further, since the double-sided pressure-sensitive adhesive sheet 12 is partially exposed in the first and second cutouts 14 and 16, the double-sided pressure-sensitive adhesive sheet 12 can be pressed firmly and comfortably to peel off the brittle material 10. .
[0020]
In the above description, the case where the brittle material 10 is held by the fixed table 22 and the brittle material 10 is peeled from the double-sided pressure-sensitive adhesive sheet 12 together with the hard plate 11 has been described, but the present invention is limited to this. Instead, for example, after the hard plate 11 is held by the fixed table 22 and the double-sided pressure-sensitive adhesive sheet 12 is peeled from the hard plate 11 together with the brittle material 10, the double-sided pressure-sensitive adhesive sheet 12 may be peeled off from the brittle material 10. However, the method of peeling the interface between the brittle material 10 and the double-sided pressure-sensitive adhesive sheet 12 is advantageous in that the number of steps can be reduced.
[0021]
Moreover, although the case where the pin 23 as the stress applying means 24 is pushed up from the lower part of the fixed table 22 has been described, the present invention is not limited to this, the pin is pressed from the upper part of the fixed table 22, the fixed table 22 is moved, The brittle material 10 may be peeled off by moving both the fixed table 22 and the holding means 24. In short, the present invention suffices if the stress applying means 24 can be moved relative to the exposed portion of the double-sided pressure-sensitive adhesive sheet 12 located in the notches 14 and 16 so as to peel the brittle material 10.
[0022]
Further, the pin 23 constituting the stress applying means 24 is not limited to the illustrated configuration example, and stress can be applied to the double-sided pressure-sensitive adhesive sheet 12 in the first and second cutout portions 14 and 16. For example, a hook or a chuck may be used instead.
[0023]
Further, although compressed air A is used as the peeling promoting means, a liquid such as water, water vapor, a wire, a spatula-like thin plate, or the like may be used as long as the same action and effect can be exhibited. Good.
[0024]
Further, instead of interposing the peeling accelerating means, stress is applied to the exposed portion of the double-sided pressure-sensitive adhesive sheet 12 located in the first and second cutouts 14 and 16 so that the ends of the double-sided pressure-sensitive adhesive sheet 12 are attached. After being peeled off, an adhesive sheet having a larger area than the brittle material 10 is attached to the brittle material 10 side, and the adhesive sheet is separated from the hard plate 11 to thereby adhere the brittle material 10 from the hard plate 11. You may peel by transferring to a sheet | seat.
[0025]
Moreover, although the said brittle material 10 and the hard board 11 were stuck via the double-sided adhesive sheet 12, the said sheet | seat is an explanatory concept corresponding to the brittle material 10 having the breadth of a surface, Comprising: Includes tape.
[0026]
【The invention's effect】
According to the present invention, the double-sided pressure-sensitive adhesive sheet is arranged so as to be exposed at the first notch portion of the brittle material and the second notch portion of the hard plate, and stress is applied to the exposed portion of the double-sided pressure-sensitive adhesive sheet. By peeling the brittle material, it is possible to peel the brittle material and the double-sided pressure-sensitive adhesive sheet so that the peeling area gradually expands, and it is possible to peel the brittle material while reducing the load on the brittle material. As a result, the brittle material can be easily peeled from the hard plate, and cracks and scratches of the brittle material can be effectively avoided.
[0027]
【Example】
Below, the specific peeling method of this invention is demonstrated.
[0028]
First, a semiconductor silicon wafer 10 (with a V notch (first notch portion 14) having a size of about 2 mm) having a diameter of 200 mm and a thickness of 725 μm was used as a material to become the brittle material 10. As will be described later, the silicon wafer 10 was ground to 50 μm to obtain a brittle material. The hard plate 11 used was a glass plate 11 (soda lime glass) having a diameter of 200 mm and a thickness of 700 μm, and one end of the outer peripheral portion was shaved to form a second notch portion 16 having a size of about 2 mm.
The double-sided pressure-sensitive adhesive sheet 12 has a UV-curable pressure-sensitive adhesive layer made of an acrylic polymer having an ultraviolet-curable functional group, formed on each side of a base film 18 made of polyethylene naphthalate (PEN, thickness 25 μm) with a thickness of 20 μm. A double-sided pressure-sensitive adhesive sheet having an ultraviolet curing type on both sides was used.
First, using a tape laminator (manufactured by Lintec Corporation, Adwill RAD3500 / m12), one side of the double-sided pressure-sensitive adhesive sheet 12 is attached to the silicon wafer 10 (mirror side), and the double-sided pressure-sensitive adhesive sheet 12 is attached to the silicon wafer 10. Cutting was performed along the outer periphery (excluding the notches 14 and 16 and on the extension of the arc). Next, using a double-sided sticking device (Adwill RAD8001LA, manufactured by Lintec Corporation), the opposite adhesive surface is stuck to the glass plate 11, and the silicon wafer 10 is fixed on the glass plate 11 as shown in FIG. did.
Next, the silicon wafer 10 fixed to the glass plate 11 was mounted on a grinding apparatus (DFG-840, manufactured by Disco Corporation), and the silicon wafer 10 was ground until the finished thickness became 50 μm. Subsequently, ultraviolet rays were irradiated from the glass plate 11 side using an ultraviolet irradiation device (manufactured by Lintec Corporation, Adwill RAD2000 / m8), and both the pressure-sensitive adhesive layers 19 and 19 ′ of the double-sided pressure-sensitive adhesive sheet 12 were cured. .
Next, as shown in FIG. 3, the silicon wafer 10 and the glass plate 11 are turned upside down, and the silicon wafer 10 is placed and held on the fixed table 22. It moved to the vicinity of the 1st and 2nd notch parts 14 and 16, the double-sided adhesive sheet 12 in the 1st and 2nd notch parts 14 and 16 was lifted with the pin 23, and stress was added. At this time, when a gap S was generated between the silicon wafer 10 and the double-sided pressure-sensitive adhesive sheet 12, compressed air A as a peeling accelerating means was interposed in the gap S from the nozzle 26.
In this way, the pin 23 was moved upward while the compressed air A was interposed, and the silicon wafer 10 was peeled from the double-sided pressure-sensitive adhesive sheet 12. The silicon wafer 10 could be peeled off from the glass plate 11 without being damaged.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing a state before a brittle material to which the method of the present invention is applied is attached to a hard plate via a sheet.
FIG. 2 is a schematic cross-sectional view showing a state where a brittle material and a hard plate are attached.
FIG. 3 is a cross-sectional view showing a state before a brittle material and a hard plate are peeled off.
FIG. 4 is an enlarged cross-sectional view showing an intermediate state in which a brittle material and a hard plate are peeled off.
[Explanation of symbols]
10 Brittle materials (semiconductor silicon wafers)
11 Hard plate (glass plate)
DESCRIPTION OF SYMBOLS 12 Double-sided adhesive sheet 14 1st notch part 16 2nd notch part 21 Peeling device 22 Fixed table 23 Pin 24 Stress applying means 26 Nozzle A Compressed air (peeling promotion means)

Claims (5)

In the method of exfoliating a brittle material having a first notch on the outer periphery, while being fixed to a hard plate via a double-sided adhesive sheet,
The hard plate has a second cutout portion of the same shape in the first cutout portion on the outer periphery,
The double-sided pressure-sensitive adhesive sheet is disposed so that the first and second cutout portions face each other and are exposed to the respective cutout portions, and a brittle material is stuck and fixed to a hard plate through the first and second cutout portions. A brittle material peeling method comprising applying stress to an exposed portion of a double-sided pressure-sensitive adhesive sheet in a region of first and second notch portions to peel the brittle material.   2. The method for peeling a brittle material according to claim 1, wherein a peeling promoting means is interposed between the double-sided pressure-sensitive adhesive sheet and the brittle material when the brittle material is peeled off.   The brittle material peeling method according to claim 1, wherein the brittle material is a semiconductor wafer, and the first notch is a V-notch.   4. The brittle material peeling method according to claim 3, wherein the semiconductor wafer is affixed to the hard plate and then the release surface is ground and processed into a thin thickness. A unit in which a brittle material having a first notch on the outer periphery is bonded and fixed to a hard plate having a second notch of the same shape in the first notch via a double-sided adhesive sheet More, in a peeling apparatus for peeling the brittle material,
A fixed table for fixing the brittle material or hard plate side of the unit;
A peeling device comprising stress applying means capable of applying stress to a double-sided pressure-sensitive adhesive sheet portion where front and back surfaces are exposed in the first and second cutout regions.

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