JP2003260659A - Manufacturing method of retaining member for object to be polished and manufacturing method of plate-shaped body for retaining member for object to be polished - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retaining member for an object to be polished, capable of fully exhibiting reinforcing effects of a sheet-like fibrous substrate, and capable of doing little damage on the peripheral surface of the object to be polished in a polishing process. <P>SOLUTION: A plate-shaped body formed by heating and pressing a plurality of overlaid sheets of the thermosetting resin impregnated sheet-like fibrous substrates and thermosetting resin un-impregnated sheet-like fibrous substrates (prepregs) is processed into the retaining member for the object to be polished, so that the contents of sheet-like fibrous substrates can be increased. Thus, the retaining member for the object to be polished with significantly high reinforcing effects can be achieved. Preferably, the sheet-like fibrous substrates are constituted of organic fiber. More preferably, they are alamido fiber non- woven cloths. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION In the manufacturing process of silicon wafers, hard disks, etc., there is a step of polishing the surfaces of these. According to the present invention, in the polishing step, a silicon wafer,
The present invention relates to a method for manufacturing a holding material for holding an object to be polished such as a hard disk.

[0002]

2. Description of the Related Art The above-described object-holding material has a structure in which one or a plurality of through holes for holding an object to be polished are formed in a disk around which a driving gear is formed. The object to be polished is fitted into the through hole, mounted on a polishing apparatus, and the holding member is driven in a plane to polish the object to be polished.

Conventionally, such a material-holding material for an object to be polished is composed of a plate-shaped body obtained by processing a thermosetting resin laminated plate. The thermosetting resin laminate is a glass fiber woven fabric-based epoxy resin laminate, an aramid fiber nonwoven fabric-based epoxy resin laminate, a cotton fabric-based phenol resin laminate, and the like. The laminated plate for constituting the material to be polished is generally prepared by impregnating a base material such as glass fiber woven cloth, aramid fiber non-woven cloth or cotton cloth with a thermosetting resin containing no inorganic or organic particles, and drying the resulting prepreg. A single prepreg or a plurality of superposed prepregs are heat-pressed and manufactured. These laminated plates are processed into an object-to-be-polished material as described above and used for polishing silicon wafers, hard disks and the like.

[0004]

The material for holding the object to be polished is
It is required to have rigidity that can securely hold the object to be polished without bending during use. Further, as the quality and performance required of the object to be polished become higher, it is required that scratches (polishing scratches) are not generated on the object to be polished.

Conventionally, a laminated plate which is processed into a material for holding an object to be polished is liable to be rich in resin because it is manufactured by stacking prepregs and molding by heating and pressing, so that the rigidity cannot be increased.
By reducing the impregnating resin of the prepreg, the reinforcing effect of the sheet-like fiber base material can be exerted and the rigidity can be increased, but the impregnating operation is performed by immersing the sheet-like fiber base material in the resin varnish, so the amount of impregnating resin is reduced. There is a limit to that.

The problem to be solved by the present invention is to provide a material for holding an object to be polished, which can sufficiently exert the reinforcing effect of a sheet-shaped fiber base material.

Further, since the hardened thermosetting resin rich layer is present on the wall surface of the through hole for holding the object to be polished, the object to be polished which has been processed into a laminated plate has the object to be held fitted into the through hole. During the polishing operation, the peripheral surface collided with the hard through-hole wall, and the peripheral surface of the object to be polished was easily scratched.

The next problem to be solved by the present invention is to provide an object-to-be-polished material which does not cause scratches on the peripheral surface of the object to be polished.

[0009]

In order to solve the above-mentioned problems, the production method according to the present invention comprises a thermosetting resin-impregnated sheet-like fiber base material (prepreg) and a thermosetting resin-unimpregnated sheet-like fiber base material. It is characterized in that a plate-shaped body obtained by heating and pressurizing a plurality of sheets obtained by stacking is processed into a material for holding an object to be polished.

According to the above-mentioned manufacturing method, the molten thermosetting resin in the prepreg permeates into the resin-unimpregnated sheet-shaped fiber base material at the time of heat and pressure molding, so that the plate-like body having a small resin content as a whole. Can be easily manufactured. Since the resin content can be reduced, the reinforcing effect of the sheet-shaped fiber base material can be sufficiently exerted, and the object-to-be-polished material holding material having high rigidity can be obtained.

The object-to-be-polished material whose resin content is suppressed as described above has a small amount of resin on the wall surface of the through hole for holding the object to be polished. As a result, the wall surface of the through hole is in a state where the fibers of the sheet-shaped fiber base material are exposed or easily exposed. Therefore, when the organic fiber is selected as the fiber constituting the sheet-shaped fiber base material, the soft organic fiber is exposed on the wall of the through hole of the workpiece holding material, not the hard thermosetting resin. Therefore, it is possible to reduce the impact when the peripheral surface of the object to be polished collides with the wall of the through hole and prevent the peripheral surface of the object to be polished from being scratched.

In particular, when an organic fiber non-woven fabric is selected as the sheet-like fiber base material, it is difficult to prepare a prepreg having a low resin content because the base material is porous, and therefore, an object to be polished having a low resin content is prepared. It was difficult to manufacture a holding material. However, according to the present invention, even in such a case, it is possible to suppress the resin content and easily manufacture a highly rigid object-holding material. Moreover, since the organic fibers forming the non-woven fabric are exposed on the wall surface of the through hole for holding the object to be polished, it is possible to suppress scratches generated on the peripheral surface of the object to be polished.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the method according to the present invention is a plate-like body obtained by heat-pressing a plurality of sheets obtained by superposing a resin-impregnated sheet-like fiber base material and a resin-unimpregnated sheet-like fiber base material. Is processed to produce an object-to-be-polished material.

The fibers constituting the sheet-shaped fiber base material may be inorganic fibers such as glass fibers or organic fibers if a material for holding an object to be polished having a high rigidity is manufactured with a reduced resin content. It may be a fiber. However, in addition, in order to provide a cushioning effect to the wall surface of the through hole of the material to be polished so that scratches do not occur on the peripheral surface of the material to be polished, organic fibers are selected as the fibers constituting the sheet-shaped fiber base material. To do. The organic fibers are preferably aramid fibers, high-strength organic fibers such as aromatic polyester fibers and polybenzoxazole fibers. In addition, polyester fibers and the like can also be used. A sheet-like fiber base material in which these fibers are woven or non-woven is used. The non-woven fabric is manufactured by paper-making a chop obtained by cutting these single fibers into a predetermined length or a pulp obtained by beating the chop. Of the organic fibers, the selection of aramid fibers is especially preferred. The reason is that aramid fibers have higher tensile strength than general organic fibers, and can improve the durability of the material-to-be-polished material and extend its service life. Furthermore, there are two types of aramid fibers, para-type and meta-type. Para-type aramid fibers have higher mechanical properties (tensile strength, etc.) of the fibers themselves than meta-type aramid fibers. It is suitable for suppressing wear and wear of the holding material and extending the life. The para-aramid fiber is less hygroscopic than the meta-aramid fiber, and is suitable for a polishing environment with water. As the para-aramid fiber, poly p-phenylene terephthalamide fiber and poly p-phenylene diphenyl ether terephthalamide fiber are commercially available, and these are common.

The thermosetting resin with which the sheet-shaped fiber base material is impregnated is not particularly limited to phenol resin, epoxy resin, polyester and polyimide. However, thermosetting resins with relatively high heat resistance such as phenolic resins and polyimides (for example, resins that have a high density in the molecular skeleton, such as benzene nuclei, that do not directly participate in adhesion) are hard Since the adhesiveness is relatively low, the interface between the base material and the resin is easily peeled off during polishing, or the resin itself is easily broken or worn. For this reason, it is preferable to use an epoxy resin as the thermosetting resin.

The plate-like body for holding the object to be polished is formed by stacking at least one sheet of fibrous base material impregnated with thermosetting resin and at least one sheet of fibrous base material not impregnated with thermosetting resin. A plurality of sheets are covered with a release film, sandwiched between mirror surface plates, and heated and pressed between press hot plates. Depending on the polishing conditions such as the type and thickness of the object to be polished, the number of sheets of sheet-shaped fiber base material to be stacked is changed. Further, the resin content of the plate-like body is appropriately adjusted by changing the number of sheets of the thermosetting resin-impregnated sheet-shaped fiber base material and the thermosetting resin-unimpregnated sheet-shaped fiber base material used.

[0017]

EXAMPLES The present invention will be described below with reference to examples. The invention is not limited by these examples. The following were prepared as a sheet-shaped fiber base material. [Aramid fiber non-woven fabric substrate A] Para-type aramid fiber (poly-p-phenylene 3,4-diphenyl ether terephthalamide fiber) chop (fiber diameter: 1.5 denier, fiber length: 3 mm, Teijin "Technola") Papermaking, and
Water-soluble epoxy resin binder (glass transition temperature 110
Unit weight 60g / m ²
Of non-woven fabric. The compounding mass ratio of para-aramid fiber / resin binder is 90/10. [Aramid fiber nonwoven fabric substrate B] Para-aramid fiber (poly-p-phenylene terephthalamide fiber) chop (fiber diameter: 1.5 denier, fiber length: 5 mm, "Kevlar" manufactured by DuPont) and para-aramid fiber pulp ( Fiber diameter: 0.1
Denier, fiber length: 1 mm, DuPont's "Kevlar") and meta-aramid fiber chops (fiber diameter: 3 denier, fiber length: 6 mm, softening temperature 280 ° C, Teijin's "Conex") were mixed and mixed. Water-soluble epoxy resin binder (glass transition temperature 110 ° C) is sprayed, heated and dried, and then heat-compressed by passing it between a pair of hot rolls to heat-bond the meta-aramid fiber chop to the para-aramid fiber chop. It is a non-woven fabric. Unit mass 70g
/ M ² , the compounding mass ratio of para-aramid fiber chop / para-aramid fiber pulp / meta-aramid fiber chop / epoxy resin binder is 58/17/8/17. Hereinafter, the aramid fiber nonwoven fabric substrate A is abbreviated as the substrate (A), and the aramid fiber nonwoven fabric substrate B is abbreviated as the substrate (B).

The following were prepared as prepregs. First, a bisphenol A type epoxy resin varnish (A) containing dicyandiamide as a curing agent and 2-ethyl-4methylimidazole as a curing accelerator was prepared. The above base materials (A) and (B) were impregnated with the varnish (A) and dried by heating to obtain a prepreg. Each prepreg has a thickness of 0.1 mm when heat-pressed.
The resin impregnation amount was adjusted so that Hereinafter, the prepreg obtained by impregnating the substrate (A) with the varnish (A) and dried by heating is referred to as the prepreg (A), and the prepreg obtained by impregnating the substrate (B) with the varnish (A) and dried by heating is referred to as the prepreg (B). To do.

Example 1 One sheet of prepreg (A) and one sheet of substrate (A) were alternately laminated, and four sheets of prepreg (A) and four sheets of substrate (A) were piled up as a whole, and this was used as a release film ( It is covered with a polypropylene film having a thickness of 50 μm and is sandwiched between mirror-finished plates. A plurality of sets of this composition are stacked and heat-pressed between press hot plates through a cushioning material made of a kraft paper layer having a thickness of 10 mm to obtain a thickness of 0.6.
A mm laminate was obtained. This laminated plate was processed into a material for holding an object to be polished. This object-to-be-polished material is a disc having a diameter of 10 inches with a gear formed on the periphery thereof, and four 3.5-inch diameter through holes for fitting the object to be polished are provided on the plate surface. is there.

Example 2 The prepreg (B) and the base material (B) were alternately laminated one by one, and four prepregs (B) and four base materials (B) were laminated as a whole.
Through the same steps as in Example 1, a material to be polished-holding material having a thickness of 0.6 mm was obtained.

Conventional Example 1 Six prepregs (A) were stacked to form a workpiece-holding material having a thickness of 0.6 mm in the same manner as in Example 1.

Conventional Example 2 Six prepregs (B) were stacked to form a workpiece holding material having a thickness of 0.6 mm in the same manner as in Example 1.

Polishing work was carried out by using the object-holding material of each of the above examples and the conventional example. The object to be polished is a 3.5-inch aluminum hard disk. Table 1 shows the results of evaluation of the aramid fiber content (mass%), the bending elastic modulus, and the degree of scratches generated on the peripheral surface of the object to be polished in the polishing step of each material to be polished. The presence / absence of scratches on the peripheral surface of the object to be polished is determined by the defect rate in 1000 batches of polishing work (1 batch is equipped with 5 pieces of the object-to-be-polished material in the polishing device and 20 hard disks are polished). Show. The service life of the material to be polished is judged by the wear level of the gear part, and the number of batches that can be repeatedly used is investigated.
The index is set to 00 (the larger the index, the longer the service life).

[0024]

[Table 1]

[0025]

EFFECTS OF THE INVENTION As is clear from Table 1, the object-holding material according to the production method of the present invention has a high rigidity because the resin content is suppressed and the content of the sheet-shaped fiber base material is large. Deflection at is small. Here, if a sheet-shaped fiber base material composed of organic fibers is selected as the sheet-shaped fiber base material impregnated with the thermosetting resin, it is possible to prevent the peripheral surface of the object to be polished from being scratched during the polishing operation. be able to. The production yield of the object to be polished can be improved, and the cost can be significantly reduced. Furthermore, if aramid fiber is selected as the organic fiber, the reinforcing effect of the high-strength aramid fiber is sufficiently exerted, and the durability against wear of the gear part is particularly enhanced, so that the use of the object-holding material while maintaining the above effect It is also possible to extend the life.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B29K 105: 08 B29K 105: 08 B29L 9:00 B29L 9:00 F term (reference) 3C058 AA07 CB02 DA02 DA06 DA17 4F204 AA36 AA39 AB03 AD06 AD16 AG03 AH33 FA01 FB01 FB11 FB22 FG02 FG09 FN11 FN15

Claims (5)

[Claims] 1. A plate-shaped body obtained by heat-pressing a plurality of sheets of a thermosetting resin-impregnated sheet-shaped fiber base material and a thermosetting resin-non-impregnated sheet-shaped fiber base material, which are used as a material to be polished. A method of manufacturing a material for holding an object to be polished, which comprises processing. 2. The method for producing an object-to-be-polished material according to claim 1, wherein the sheet-shaped fiber base material is made of organic fibers. 3. The method for producing a material for holding an object to be polished according to claim 1, wherein the sheet-shaped fiber base material is made of organic fibers, and a part or the whole of the sheet-shaped fiber base material is a non-woven fabric. 4. The method for producing a material-to-be-polished material according to claim 2 or 3, wherein the organic fiber is an aramid fiber. 5. A plate-like body is obtained by heat-pressing a plurality of sheets of a thermosetting resin-impregnated sheet-shaped fiber base material and a thermosetting resin-unimpregnated sheet-shaped fiber base material that are superposed on each other. A method for manufacturing a plate-like body for a material for holding an object to be polished.