JP2002059362A - Polished work holding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polished work holding material to prevent growth of scratches of a polished article even though it is thin concerning the polished work holding material as a jig to polish the thin plate type polished work such as a silicon wafer, etc. SOLUTION: This holding material is furnished with a base layer B made by soaking a base material made of organic fiber in resin and a surface film layer F accumulated on a surface of this base layer B, and this surface film layer F is made of an organic resin film of a tensile elastic modulus of more than 4000 N/mm2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hard disk,
The present invention relates to an object holding material used as a jig when polishing a thin plate-shaped object to be polished such as a silicon wafer or a liquid crystal glass, and in particular, it can prevent scratches from being generated on the surface of the object to be polished while being thin. The present invention relates to an object-to-be-polished holding material as described above.

[0002]

2. Description of the Related Art In recent years, with the development of electronic devices, a wide variety of electronic components have been manufactured. In order to reduce the thickness or size of electronic devices, the technology of forming electronic components on minute chips has been developed. Was.

For example, a typical IC chip as a chipped electronic component uses, for example, a thin film forming technology such as ion plating, vapor deposition and sputtering, an etching technology, a printing technology, and a photographic technology on the surface of a silicon wafer. It is manufactured by forming an electronic circuit including several electronic elements such as a transistor, a triac, a resistor, a capacitor, and a coil, and then cutting the chip into small chips.

[0004] The surface of the silicon wafer used for manufacturing the chip component is required to have a very high degree of flatness.
For example, it is finished by precision finishing using a wrapping machine.

In this lapping, for example, as shown in FIG. 3, for example, a circular thin plate-shaped sliced silicon wafer has a tooth mold 1 formed on the periphery thereof, and a thin plate-like polishing object W is fitted therein. At least one work holding hole 2
Are fitted as workpieces W into the workpiece holding holes 2 of the sheet-like workpiece holding material H having the through holes.

[0006] Then, the tooth mold 1 of the workpiece holding material H is polished.
Meshes with the internal gear provided on the peripheral portion of the table of the lapping machine and the tooth form 1 of the other holder H, and the holder H and the holder held by the same. W rotates on the table of the lapping machine and the abrasive to perform polishing.

Conventionally, as the object-to-be-polished holding material H, a prepreg in which a thermosetting resin or a thermoplastic resin is impregnated on a substrate made of a woven or non-woven fabric such as glass fiber, polyester fiber or aramid fiber is laminated. A laminated plate is used, and a polished-piece holder H made of a glass fiber having excellent mechanical strength is used for a thin polished workpiece.

[0008]

However, the holding member H to be polished made of glass fiber is peeled off at the interface between the glass fiber and the resin by mechanical force acting on the surface of the tooth mold 1 during polishing. Tends to occur, and the peeled glass fibers are finely crushed and sandwiched between the workpiece W and the table or abrasive of the lapping machine, thereby causing a polishing scratch called a scratch on the surface of the workpiece W. is there.

When organic fibers, such as polyester fibers and aramid fibers, which have a stronger bonding force between the base material and the resin than glass fibers and are less fragile due to the lower brittleness of the fibers, are used. Fiber debris is less likely to be generated from the tooth form 1 of the holding material H, and even if organic fiber debris is generated, there is no problem of scratching due to softness. Since the mechanical strength, particularly the rigidity, is lower than that of the material H, the workpiece W is deformed in the thickness direction and enters the periphery of the work holding hole 2 so that one surface of the workpiece W is excessively polished or polished. Or not to be
A bias in polishing may occur.

For this reason, the polished work holding material H using the organic fiber is practically used only when the polished work W is considerably thick and the polished work holding material H may be considerably thickened. It is the present situation.

In recent years, the demand for thinner electronic components has been further escalated, and in many cases, a thinner material has to be used as the holding material H for the object to be polished. Material to be polished H
Is often used.

However, the higher the flatness of the object to be polished, the higher the degree of flatness is required. Therefore, the provision of the object to be polished H, which is thin and does not cause scratches, has been proposed.
This kind is strongly demanded in the industry.

An object of the present invention is to solve the latest technical problem and to provide a holder for a polished work which is thin but can prevent scratches from being generated on the surface of the polished work. Is what you do.

[0014]

In order to achieve this object, the object-to-be-polished holding material according to the present invention has at least one opening in which a tooth shape is formed on the periphery and a thin plate-shaped object to be polished is fitted. In a sheet-like object-to-be-polished holding material in which a work holding hole is penetrated, the object-to-be-polished holding material is a base layer obtained by impregnating a resin made of an organic fiber with a resin, and a surface laminated on the surface of the base layer And a film layer, and the surface film layer is made of an organic resin film having a tensile modulus of 4000 N / mm ² or more.

[0015] According to the present invention, since a base layer made of organic fibers is impregnated with a resin and a specific surface film layer is laminated on the surface of the base layer, the base layer made of glass fibers is As a result, it is possible to obtain a polished work holding material having a high mechanical strength, while having a small thickness, similarly to the conventional polished work holding material impregnated with resin. As a result, the polished work enters one side of the polished work holding material during polishing. Can be prevented.

In addition, as the base material, an organic fiber which has a stronger bonding force with the resin than glass fiber and is hard to break because of low brittleness is used. No fiber debris is generated when it comes into contact with the tooth mold of another holder for the object to be polished.

In the present invention, the surface film layer is formed of an organic resin film having a tensile modulus of elasticity of 4000 N / mm ² or more. As a result, it is more difficult to generate debris than the base material when it comes into contact with the tooth mold of the material. As a result, it is possible to prevent scratches from being formed on the polished object by debris coming out of the polished object holding material.

In addition, if it adheres to the object to be polished like glass fiber, there is no possibility of affecting the electrical properties of the object to be polished, so that the problem of the adhesion of impurities (so-called contamination) can be solved.

Hereinafter, in describing the present invention in detail,
The base material suitably used in the present invention, the resin to be impregnated into the base material, the surface film layer, the laminated structure of the base layer and the film layer, and the like will be described in more detail.

First, as the organic fibers constituting the substrate,
Organic fibers may be used, and natural fibers, synthetic fibers, or semi-synthetic fibers may be used. However, considering quality stability, mechanical strength and the like, it is most preferable to use synthetic fibers among them.

The synthetic fibers include, for example, polyester fibers such as polyethylene terephthalate fiber, polyimide fiber and polyethylene naphthalate fiber, vinylon (polyvinyl alcohol-based synthetic fiber), aramid fiber, polycarbonate fiber and the like having excellent mechanical strength. Among them, polyester fibers and vinylon having high tenacity are more preferable.

The structure of the substrate made of this synthetic fiber is not particularly limited, but may be a woven or non-woven fabric similar to a conventional substrate. 30 to 300 g / m ^{2 in} consideration of reinforcing reliability, etc.
And particularly preferably 50 to 150 g / m ² .

In the present invention, the resin impregnated in the substrate may be a thermosetting resin or a thermoplastic resin.

Examples of the thermosetting resin include epoxy resin, melamine resin, unsaturated polyester resin, polyurethane resin, phenol resin, polyimide resin, alkyd resin, diacrylate resin and the like.

Further, as the thermoplastic resin, polyamide resin, polysulfide resin, polyacetal resin,
Examples thereof include a polyolefin-based resin, a polyester resin, and a polyurethane resin.

The amount of the resin to be impregnated into the base material is not particularly limited, but is preferably 50 to 250 parts by weight based on 100 parts by weight of the base material. If the resin is less than 50 parts by weight with respect to 100 parts by weight of the base material, during lamination molding, in order to ensure interlayer adhesion, it is necessary to increase the molding pressure, so that the molded product tends to be distorted, It is not preferable because warpage and twisting may occur significantly. on the other hand,
If the resin exceeds 250 parts by weight with respect to 100 parts by weight of the base material, the resin content is large, so that the abrasion resistance is reduced, the flow of the resin is increased in the molding step, and molding becomes difficult, It is not preferable because the variation in thickness is likely to be large.

The method of impregnating the base material with the resin is not particularly limited, and a conventional method of impregnating the base material with the resin, for example, a method such as brushing, roller coating, spray-up, or coating may be employed. good.

The surface film layer used in the present invention is not particularly limited as long as it is composed of an organic resin film having a tensile modulus of 4000 N / mm ² or more.
Examples of such a film having a high elastic modulus include polyethylene terephthalate (trade name: Lumilar, manufactured by Toray, product type S1)
0, tensile modulus 4000 N / mm ² ), polyethylene naphthalate (manufactured by Teijin, trade name: Teonex, tensile modulus 5400 N / mm ² ), aramid resin (manufactured by Asahi Kasei, trade name Aramica, product type R, tensile modulus 1200 N / m
m ² ), polyimide resin (manufactured by Toray DuPont, trade name Kapton, product type E, tensile modulus 6000 N / m)
m ² ) (Kanebuchi Chemical Co., Ltd., trade name Apical, type NPI, tensile modulus 4200 N / mm ² ) (Ube Industries, trade name Upilex, type S, tensile modulus 9000 N / m)
m ² ) are commercially available.

If the tensile modulus of the surface film layer is less than 4000 N / mm ² , the rigidity of the holding material for the object to be polished is insufficient, and the object to be polished may be undesirably sunk.

The laminated structure of the base layer and the surface film layer is not particularly limited. For example, a two-layer structure in which the surface film layer is laminated on one side of the base layer, and the base layer is disposed at the center, It is possible to adopt a three-layer structure or the like in which the surface film layers are stacked one upon another.

However, taking into account the reduction in thickness and the balance of mechanical strength between the front and back sides, in these laminated structures, the base layer is disposed at the center, and the surface film layers are laminated on both sides thereof. It is desirable to adopt the three-layer structure described above. However, since this three-layer structure may be a three-layer structure at the product stage, there is one layer between the front and back surface film layers.
Of course, those formed by heating and pressing with a layer of prepreg-like base layer in between are included, but in order to obtain the required thickness, multiple prepreg-like base layers are stacked and laminated between the front and back surface film layers In some cases, the plurality of base layers are formed into an integrated layer by heating and pressing.

According to this three-layer structure, when an external force acts to bend the holder for the object to be polished in the thickness direction, the external force acts as a tension on the surface film layer on one surface and the surface on the opposite surface. Acts as a plane pressure on the film layer. Here, the surface film layers on both front and back sides have a tensile modulus of 4000.
Since it is made of a high elastic modulus film of N / mm ² or more, the deformation in the plane direction is small, and the whole polished work holding material has a modulus of elasticity against bending stress of a conventional polished work holding material made of glass fiber reinforced resin. Can be as high as normal.

The thickness of the surface film layer is not particularly limited, but is preferably from 30 to 175 μm, and more preferably from 50 to 150 μm. When the thickness of the surface film layer is less than 30 μm, it is not preferable because required rigidity cannot be obtained.
If it exceeds 5 μm, there is a possibility that peeling may occur on the lamination surface with the base layer, which is not preferable.

The base layers are combined, or the base layer and the surface film layer are superposed on each other, and are heated and pressurized.
Although it is possible to adhere to each other by using the resin of the base layer, if necessary, an adhesive layer may be interposed between the base layer and the surface film layer, and the two may be adhered to each other with this adhesive layer.

This adhesive layer may be made of a thermosetting resin or a thermoplastic resin.

Examples of the thermosetting resin include epoxy resin, melamine resin, unsaturated polyester resin, polyurethane resin, phenol resin, polyimide resin, alkyd resin, diacrylate resin and the like.

Examples of the thermoplastic resin include polyamide resin, polysulfide resin, polyacetal resin, polyolefin resin, polyester resin, and polyurethane resin.

The thickness of the adhesive layer is preferably 5 to 50 μm, and if it is less than 5 μm, there is a possibility that a sufficient adhesive strength may not be obtained, and if it exceeds 50 μm, it is not preferred. It is not preferable because the flow tends to increase, the molding becomes difficult, and the thickness variation of the molded product tends to increase.

The adhesive layer may be formed by applying a liquid adhesive to the base layer and / or the surface film layer using a brush, a roller, or the like. It is desirable to use one formed in a sheet shape.

In order to increase the adhesive strength between the surface film layer and the adhesive layer or the base layer, the surface of the surface film layer may be subjected to a roughening treatment such as a sand treatment or a corona treatment or a primer treatment.

[0041]

As described above, the object-to-be-polished holding material of the present invention comprises a base layer obtained by impregnating a resin made of an organic fiber with a resin, and a surface film layer laminated on the surface of the base layer. Moreover, this surface film layer has a tensile modulus of 4000.
Since it is composed of an organic resin film of N / mm ² or more, it is possible to obtain an effect that even if it is thin, rigidity equivalent to or higher than that of a conventional holder for a polished work using glass fiber as a base material can be obtained. .

In the present invention, in forming the base layer, the substrate formed of glass fibers has a weak bonding force with the resin and is easily peeled off, while the organic fibers are formed of a resin compared to the glass fibers. It has a strong bonding force with and is difficult to peel off, and in addition, the organic fiber is
Since it is extremely hard to break, there is also obtained an effect that no fiber debris is generated when it comes into contact with the internal gear of the polishing apparatus or the tooth form of another holder for the object to be polished during polishing.

Further, in the present invention, the surface film layer is formed of an organic resin film having a tensile modulus of elasticity of 4000 N / mm ² or more. Since the debris is less likely to be generated than the substrate when coming into contact with the mold, an effect is obtained that no debris is generated not only from the base layer but also from the surface film layer from the holder for the object to be polished during polishing.

[0044]

Embodiments of the present invention, comparative examples, and conventional examples will be specifically described below with reference to the drawings.

In the present invention, a polyester non-woven fabric (manufactured by Hirose Paper, product number 05TH-60) having a basis weight of 60 g / m ² and a thickness of 110 μm is used as a base material in the following examples. 5 parts by weight of dicyandiamide,
0.5 parts by weight of 2-ethyl-4-methylimidazole as a curing accelerator and bisphenol A type epoxy resin 10
After impregnating with an epoxy resin varnish consisting of 0 parts by weight,
It was dried by a known method to obtain a prepreg for forming a base layer.

The amount of the resin adhered to the base material was determined by
The amount of the resin was 170 parts by weight with respect to the parts by weight, and the prepreg was adjusted so that the layer thickness after the heat and pressure molding was 0.1 mm.

Example 1 Seven prepregs were stacked as a base layer, and a tensile modulus of elasticity of 5400 N / mm ² and a thickness of 50 μm were formed on both front and back surfaces.
After laminating a polyethylene naphthalate film (manufactured by Teijin, trade name: Teonex) as the surface film layers F, F, the laminated product is sandwiched between mirror plates, and heated and pressed between hot press plates to form a cross section shown in FIG. Base layer B schematically shown in the figure
, And a laminated board having a thickness of 0.82 mm in which the surface film layers F, F were laminated on both front and back surfaces thereof was obtained.

Example 2 Six prepregs were stacked as a base layer, and a tensile modulus of elasticity of 5400 N / mm ² , a thickness of 100
After laminating a polyethylene naphthalate film (manufactured by Teijin, trade name: Teonex) having a thickness of μm as surface film layers F, a laminated plate having a thickness of 0.82 mm was obtained in the same manner as in Example 1.

Example 3 Seven prepregs were stacked as a base layer, and a tensile modulus of elasticity of 4000 N / mm ² and a thickness of 50 μm were formed on both front and back surfaces.
m of polyethylene terephthalate film (manufactured by Toray Co., Ltd., trade name: Lumirror, type S10) as the surface film layers F, F, and in the same manner as in Example 1, a thickness of 0.82
mm was obtained.

Example 4 Six prepregs were stacked as a base layer, and a tensile modulus of elasticity of 4000 N / mm ² , a thickness of 100
μm polyethylene terephthalate film (Toray,
Product name Lumirror, product type S10)
Then, in the same manner as in Example 1, a thickness of 0.8
A 2 mm laminate was obtained.

Example 5 Seven prepregs were stacked as a base layer, and a tensile modulus of elasticity of 12000 N / mm ² and a thickness of 50 were applied on both front and back surfaces.
μm aramid film (made by Asahi Kasei, trade name Aramica,
(Type R type) were laminated as surface film layers F, F, and a laminated plate having a thickness of 0.82 mm was obtained in the same manner as in Example 1.

Example 6 Six prepregs were stacked as a base layer, and a tensile modulus of elasticity of 12000 N / mm ² and a thickness of 10
After laminating a 0 μm aramid film (Aramika, product name: R-type, manufactured by Asahi Kasei Corporation) as surface film layers F, F, a laminated plate having a thickness of 0.82 mm was obtained in the same manner as in Example 1.

Comparative Example 1 Seven prepregs were stacked as a base layer, and a tensile modulus of elasticity of 3000 N / mm ² and a thickness of 50 μm were formed on both sides of the prepreg.
After laminating a polyimide film (manufactured by Toray, trade name Kapton, type H type) as surface film layers F, F,
In the same manner as in Example 1, a laminated plate having a thickness of 0.82 mm was obtained.

COMPARATIVE EXAMPLE 2 Six prepregs were stacked as a base layer, and a tensile modulus of elasticity of 3000 N / mm ² and a thickness of 100 μm were formed on both sides of the prepreg.
After laminating a polyimide film (manufactured by Toray, trade name Kapton, product type H) as surface film layers F, F, a laminated plate having a thickness of 0.82 mm was obtained in the same manner as in Example 1.

Comparative Example 3 Eight of the prepregs alone were stacked as a base layer, and the laminated product was sandwiched between mirror plates, and heated and pressed between hot press plates to obtain a laminated plate having a thickness of 0.8 mm.

Comparative Example 4 A glass cloth having a thickness of 160 μm was used as a substrate, and 5 parts by weight of dicyandiamide as a curing agent and 0.5 parts of 2-ethyl-4-methylimidazole as a curing accelerator were added to the substrate.
After impregnating with an epoxy resin varnish consisting of 100 parts by weight of a bisphenol A type epoxy resin and 100 parts by weight of a bisphenol A type epoxy resin, it was dried by a known method to obtain a prepreg.

Five prepregs were stacked, the laminated product was sandwiched between mirror plates, and heated and pressed between hot press plates to obtain a laminated plate having a thickness of 0.8 mm.

The tensile modulus of each of the surface film layers of Examples 1 to 6 and Comparative Examples 1 and 2 was ASTM D-882.
The measurement was performed according to the measurement method described above.

The flexural modulus of each of the laminates of Examples 1 to 6 and Comparative Examples 1 to 3 was measured in accordance with the measuring method of ASTM D790-95a. In each of the examples in which a surface film layer having a tensile elasticity of 4000 N / mm ² or more was laminated, Comparative Examples 1 and 2 in which a surface film layer having a tensile elasticity of 3000 N / mm ² was laminated and a comparative example having no surface film layer It is found to be significantly higher than those of Example 3.

[0060]

[Table 1]

Using the laminated plates of Examples 1 to 6 and Comparative Examples 1 to 4, as shown in FIG. 2, a tooth mold 1 was formed on the periphery, and workpieces were held at a plurality of positions equidistant from the center. Hole 2
The polished object holding material was formed, and was used for polishing a silicon wafer using a lapping machine. The presence or absence of intrusion and the presence or absence of scratches on the surface of the polished object were observed. In the polished work holding material using, the polished work was found to have slipped into one side of the polished work holding material.
No occurrence of infiltration was observed in the holder for the object to be polished, which was composed of the above laminated plate.

Further, it was observed that scratches did not occur on the surface of the lapping-finished object to be polished in the holder for the object to be polished composed of the laminated plates of Examples 1 to 6.

On the other hand, it was observed that scratches occurred on the surface of the object to be polished, which had been subjected to lapping using the object-to-be-polished holding material made of the laminated plate of Comparative Example 4.

[0064]

As described above, the object-to-be-polished holding material of the present invention comprises a base layer made by impregnating a resin made of an organic fiber with a resin, and a surface film layer laminated on the base layer. Moreover, this surface film layer has a tensile modulus of 4000.
Formed of an organic resin film of N / mm ² or more,
Compared to the conventional example in which only prepregs based on organic fibers are laminated, the effect of higher rigidity is obtained, so that even if the thickness is thin, the glass fiber base material which does not sneak into the object to be polished does not occur. Thus, an effect that a polished work holding material having a rigidity equal to or higher than that of the polished work holding material can be obtained is obtained.

Further, according to the present invention, the base material is made of an organic fiber,
Since the surface film layer is made of an organic resin film, according to the present invention, the surface film layer is formed on the periphery at the time of polishing, which is distinctly different from a conventional holder for a polished object which is based on glass fiber in which chipping (deletion) easily occurs. Tooth type chipping (defect)
Therefore, the effect that scratches are not formed on the surface of the object to be polished due to chips generated by chipping does not occur.

Further, according to the present invention, since there is no chipping and no debris generated during polishing, there is also obtained an effect that the problem of the contamination of the surface of the object to be polished with impurities can be eliminated. You can do it.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing the present invention.

FIG. 2 is a plan view showing one embodiment of the present invention.

FIG. 3 is a plan view for explaining a problem in a conventional state of polishing an object to be polished.

[Explanation of symbols]

 1 Tooth mold 1 2 Work holding hole B Base layer F Surface film layer

Claims (7)

[Claims] 1. A sheet-like object-to-be-polished holding material through which at least one work holding hole into which a thin plate-like object to be polished such as a silicon wafer or a liquid crystal glass is fitted is provided. The holding material includes a base layer obtained by impregnating a resin into a substrate made of organic fibers, and a surface film layer laminated on the surface of the base layer, and the surface film layer has a tensile modulus of 4000 N / mm ² or more. An object-to-be-polished holding material, comprising an organic resin film. 2. The holder for an object to be polished according to claim 1, wherein the substrate is made of a woven or non-woven fabric of organic synthetic resin fibers. 3. The holder for an object to be polished according to claim 1, wherein the substrate is made of a polyester fiber or a vinylon fiber. 4. The resin according to claim 1, wherein the resin impregnated in the substrate comprises a thermosetting resin or a thermoplastic resin.
Item 2. A holder for an object to be polished according to item 1. 5. The organic resin film according to claim 1, wherein the organic resin film is made of polyethylene terephthalate (PET), polyimide (PI), polyethylene naphthalate (PEN) or aramid resin and has a tensile modulus of 4000 N / mm ² or more. 5. The holder for an object to be polished according to any one of 4. 6. The holder for an object to be polished according to claim 1, wherein a surface film layer is laminated on both surfaces of the base layer. 7. The holder for an object to be polished according to claim 1, wherein an adhesive layer is interposed between the base layer and the surface film layer.