JPH10261600A - Manufacture of protective sheet for semiconductor wafer, and protective sheet and die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective sheet for a semiconductor wafer which can effectively protect a semiconductor wafer and does not attach to the wafer and also provide a method for manufacturing it. SOLUTION: A synthetic resin sheet 8 is placed between an upper and a lower embossing die 5A, 5B whose recessed and projecting sections 5C, 5D are made of other material than metal such as hard synthetic resin to form an embossing pattern in the sheet 8 and then the sheet 8 is punched to a circular shape to be used as a protective sheet for a semiconductor wafer. Or, an embossing pattern is formed on a circular synthetic resin sheet made by forming on a base sheet a resin layer which melts at a lower temperature than the base sheet by the upper and the lower embossing die 5A, 5B whose recessed and projecting sections 5C, 5D are made of other material than metal and then the resin layer which melts at a lower temperature than the base sheet is heat- set to mold the embossing pattern. The manufactured sheet is used as a protective sheet for a semiconductor wafer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a protective sheet for a semiconductor wafer and a protective sheet, and more particularly to a method for manufacturing a protective sheet for a semiconductor wafer capable of facilitating a semiconductor wafer processing step and improving safety. Related to protective sheets.

[0002]

2. Description of the Related Art Conventionally, a semiconductor wafer is a thin disk having a small diameter of about 3 inches to a large diameter of about 8 inches and is cut into a desired size by a cutting machine to form a semiconductor. . In the cutting machine, a semiconductor wafer is placed on a supply section via a protective sheet. From the supply section, the semiconductor wafers are moved one by one to a cutting section by a suction cup, and the semiconductor wafer is cut by a cutter at the cutting section. It is cut to the desired size. The protective sheet is for protecting the semiconductor wafer from scratches and dust, and generally a synthetic resin laminate sheet or a smooth sheet obtained by coating a synthetic resin sheet with a release agent is used.

[0003]

In the above cutting machine,
When the semiconductor wafer is moved from the supply section to the cut section one by one by the suction cup, the protective sheet moves to the cut section without peeling off due to the close contact with the semiconductor wafer, causing a problem at the cutting stage. there were. Another problem is that when a force is applied to the stacked semiconductor wafers from above, the impact is also applied to the lower side and the number of damaged semiconductor wafers increases. SUMMARY OF THE INVENTION The present invention has been developed to solve the above-mentioned difficulties and to provide a semiconductor wafer protection sheet which is excellent in semiconductor wafer protection properties and does not adhere to the semiconductor wafer, and a method of manufacturing the same.

[0004]

Means for Solving the Problems The present invention has taken the following technical means in order to solve the above-mentioned problems and achieve the object. The synthetic resin sheet referred to here is a single sheet of a synthetic resin, a plurality of laminated sheets of a single sheet of a synthetic resin, a sheet having a resin coating on a paper surface,
It refers to nonwoven fabric alone or coated. The basic sheet refers to a basic resin sheet, paper, nonwoven fabric, or the like for performing lamination, coating, or the like. The upper and lower embossing type, in which the uneven portion is made of a material other than metal, is a type in which a hard synthetic resin film or ceramic film is formed on the surface of metal, ceramic, wood, etc. Is also included. The specific configuration is as follows.

[0005] A method of manufacturing a protective sheet for a semiconductor wafer, in which an embossing pattern is formed by arranging a synthetic resin sheet between upper and lower embossing dies made of a material other than metal, and die-cutting into a circle.

[0006] An embossing pattern is formed on a surface of a basic sheet by a vertical embossing type made of a material other than metal on a synthetic resin sheet having a resin layer that melts at a lower temperature than the basic sheet. A method of manufacturing a protective sheet for a semiconductor wafer, wherein an embossing pattern is formed by heat setting a resin layer that is melted in step (a).

A protective sheet for a semiconductor wafer in which a smooth surface is set at the center of the surface of a synthetic resin sheet and an embossing pattern is formed around the smooth surface.

An embossing pattern is formed on a circular synthetic resin sheet having a resin layer that melts at a lower temperature than the base sheet formed on the surface of the base sheet, and the resin layer that melts at a lower temperature than the base sheet is heat-set. A protective sheet for a semiconductor wafer obtained by fixing and molding an embossing pattern.

An embossing type in which the concave and convex portions are made of a material other than metal, wherein a heating means is provided inside the type.

[0010]

The present invention configured as described above has the following functions. Conventionally used protective sheets for semiconductor wafers have smooth surfaces on both sides. Therefore, if the protective sheets are interposed between the semiconductor wafers to be laminated, the protective sheet is more likely to be in close contact with the semiconductor wafer.
In the present invention, since the embossing pattern is formed on the protective sheet, the bonding area between the protective sheet and the semiconductor wafer is significantly reduced, and since there is a space, the airflow flows,
There is an effect that the protective sheet is hard to adhere to the semiconductor wafer. In addition, even if the thickness of the protective sheet is the same as the conventional one, the embossing pattern has excellent cushioning due to the unevenness on the front and back, and as a result, the force is applied from above when the semiconductor wafer is stacked. Even if it is applied, the unevenness of the embossing pattern has an effect of absorbing the impact, and can prevent the semiconductor wafer from being damaged. In the manufacturing method, the embossing type is generally made of metal. However, when embossing is performed on a synthetic resin sheet using a metal embossing type, fine metal powder adheres to the synthetic resin sheet and metal ions are formed on the synthetic resin sheet. Cannot be prevented from moving. In addition, removing metal powder and metal ions attached to the synthetic resin sheet from the synthetic resin sheet after the embossing process requires large-scale equipment and is extremely difficult. The use of a protective sheet to which these metal powders and metal ions are attached has a disadvantage that the quality of the semiconductor wafer is affected. In this regard, the present invention uses an embossing type in which the uneven surface is made of a material other than metal, so that the synthetic resin sheet can be subjected to embossing, but there is no effect of metallicity.

[0011]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a protection sheet (hereinafter referred to as a protection sheet) of a semiconductor wafer. The protective sheet 1 is made of, for example, a thin sheet of polyethylene and has a disk shape of 3 inches to 8 inches. The suction surface 1A is set in the center of the disk so that the suction disk can be sucked. 2 are formed. The unevenness 2A, 2B of the embossing pattern 2 is about 2 to 5 times the thickness of the sheet, and the shape of the pattern is arbitrary.

When the protective sheet 1 is sandwiched between the semiconductor wafers 3 and 3 stacked as shown in FIG. 2 in the above configuration, the unevenness 2A and 2B of the embossing pattern 2 support the upper semiconductor wafer 3. Since the gap 4 is formed between the upper and lower semiconductor wafers 3, the cushioning is excellent, and even if an impact is applied from the top to damage the upper semiconductor wafer 3, the impact is applied to the embossing pattern 2. Unevenness 2
Semiconductor wafer 3 which is absorbed by
Is prevented and protected. Further, as can be clearly understood from the figure, since the gap 4 is formed between the upper and lower semiconductor wafers 3 and 3 by the irregularities 2A and 2B of the embossing pattern 2, the upper semiconductor wafer 3 is sucked and moved by the suction cup. However, since the protective sheet 1 thereunder does not adhere to the semiconductor wafer 3, it does not adhere to the upper semiconductor wafer 3 and does not move. Since the suction surface 1A on which the embossing pattern 2 is not formed is set at the center of the protection sheet 1, the suction surface 1A is mechanically sucked to the suction surface 1A by a suction cup and carried on the semiconductor wafer 3 for stacking. And can be mechanically sucked and removed from above the semiconductor wafer 3 with a suction cup. The suction surface 1A is not limited to a circle, but may be, for example, a triangle or a ring. Further, depending on the embossing pattern 2 having a small height of the irregularities 2A and 2B, or depending on the shape of the pattern, the embossing pattern 2 can be adsorbed without forming the adsorption surface 1A. Further, the suction surface 1A in FIG. 1 can be an opening.

FIG. 3 is a front view of an embossing die for embossing. The embossing mold 5 is, for example, F
An upper mold 5A and a lower mold 5B formed of a hard synthetic resin (ceramic may be used) such as an RP resin molded body, and concave and convex molds 5C... When 5A is pressed to lower mold 5B, each convex mold 5D is formed so as to fit with the corresponding concave mold 5C. In the figure, reference numeral 6 denotes a heater as a heating means, which is supplied with power from a power source (not shown) via a cord 7, and the heating means 6 generates heat to form the concave and convex molds 5C,.
5D can be heated to a temperature required for heat setting the synthetic resin sheet 8. The upper mold 5A and lower mold 5B
Between the upper mold 5A and the lower mold 5B.
The embossing pattern 2 is formed on the synthetic resin sheet 8 by pressing to. In this case, when the upper and lower dies 5A and 5B of the hard synthetic resin can be heated in advance by the heating means 6, the embossing pattern 2 is heat-set by performing heating necessary for heat setting simultaneously with the embossing process. Can be. If it is difficult to heat the hard synthetic resin to the upper mold 5A and the lower mold 5B, the embossing pattern 2 is pressed, and then the synthetic resin sheet 8 taken out of the upper mold 5A and the lower mold 5B is heated with hot air, infrared rays, or the like. The shape of the embossing pattern 2 is heat-set by heating by means of (1). Of course, the embossing pattern 2 can be formed simply by pressing. In addition, the embossing process can be formed by upper and lower rollers. The material of the synthetic resin sheet 8 may be any material as long as it suits the purpose. However, in order to make the heat setting effective, a layer of a resin that is thermally melted at a lower temperature than the base sheet is formed on the surface of the base sheet. Can be formed. This makes it possible to heat-set the embossing pattern reliably even when the heating temperature of the heating means provided in the upper mold 5A and the lower mold 5B of the hard synthetic resin is relatively low. In the case where the embossing pattern 2 is formed only by pressing, if a sheet on which a soft resin coating layer is formed is used, irregularities can be effectively formed and fixed as in compression molding. If the synthetic resin sheet 8 is long, one embossing pattern 2 is formed, and the synthetic resin sheet 8 is moved one frame at a time in the longitudinal direction to form the embossing pattern 2 continuously. Thereafter, the protective sheet 1 is formed by punching into a shape as shown in FIG. The material of the hard synthetic resin mold 5 may be a single synthetic resin, but mineral powder other than metal can be mixed in terms of hardness or wear resistance. It should be noted that the present invention is not limited to the above-described configuration, and can be appropriately designed and changed according to the purpose.

[0014]

As described above, the present invention has the following excellent effects.

A. Protective sheet is embossing pattern 2
Because of the unevenness, the sheet is bulkier than the thickness of the sheet. Even if it receives an impact, the impact is absorbed by the collapse of the unevenness. There is an effect that damage can be prevented and protected.

B. Protective sheet is embossing pattern 2
Is formed bulkier than the thickness of the sheet because it is formed in an uneven shape, and the contact area of the protection sheet to the semiconductor wafer is small due to the unevenness, and the close contact is prevented by the presence of the space due to the unevenness, Since the protection sheet does not stick and move when the semiconductor wafer is moved, there is an effect that the protection sheet does not cause a trouble in the processing step of the semiconductor wafer.

C. In the production of the protective sheet, since an embossing type of a material other than metal is used, there is no possibility that metal powder or metal ions adhere to the protective sheet. As a result, the protective sheet is interposed between the semiconductor wafers and the semiconductor wafer is interposed. Even when the layers are stacked, there is an effect that no adverse effect due to metal powder or metal ions is caused on the semiconductor wafer.

D. The embossing type made of a material other than metal has an effect that metal powder and metal ions do not adhere to the protective sheet. When the heating means is installed, the embossing type can be effectively formed on the protective sheet. effective.

[Brief description of the drawings]

FIG. 1 is a plan view of a protection sheet for a semiconductor wafer.

FIG. 2 is a front view showing a use state of a protection sheet for a semiconductor wafer.

FIG. 3 is a front view illustrating a method for manufacturing a protection sheet for a semiconductor wafer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Protective sheet of semiconductor wafer 1A adsorption surface 2 embossing pattern 2A concave part 2B convex part 3 semiconductor wafer 4 gap 5 embossing type 5A upper die 5B lower die 6 heating means 7 code 8 resin sheet

Claims (5)

[Claims] 1. A method for manufacturing a protective sheet for a semiconductor wafer, comprising: forming an embossing pattern by arranging a synthetic resin sheet between upper and lower embossing dies whose uneven portions are made of a material other than metal; . 2. A synthetic resin sheet in which a resin layer that melts at a lower temperature than the base sheet is formed on the surface of the base sheet. A method for manufacturing a protective sheet for a semiconductor wafer, wherein an embossing pattern is formed by heat setting a resin layer that melts at a lower temperature than a base sheet. 3. A protection sheet for a semiconductor wafer, wherein a smooth surface is set at the center of the surface of a circular synthetic resin sheet, and an embossing pattern is formed around the smooth surface. 4. An embossing pattern is formed on a circular synthetic resin sheet having a resin layer that melts at a lower temperature than the base sheet formed on the surface of the base sheet, and the resin layer that melts at a lower temperature than the base sheet is heat-set. A protective sheet for a semiconductor wafer, characterized in that an embossing pattern is formed by doing so. 5. An embossing type wherein an uneven portion is made of a material other than metal, wherein a heating means is provided in the type.