JPH0624201B2 - Method for fixing semiconductor wafer to abutting plate - Google Patents

Description

The present invention relates to a method for fixing a semiconductor wafer to a contact plate.

More specifically, when a discrete element substrate is manufactured from a semiconductor wafer of a silicon (Si) single crystal disk shape or the like used as a discrete element (individual element) such as a transistor or a diode, the semiconductor wafer is divided into two parts. The present invention relates to a method of fixing a contact plate to a peripheral edge of a semiconductor wafer in a step of performing a divided cutting work.

[Prior Art] Conventionally, for the purpose of reducing consumption of a silicon single crystal, the present applicant has an impurity diffusion layer in which impurities are not diffused in a central portion and an impurity diffusion layer in which impurities are diffused on both sides. Propose a method for manufacturing a substrate for discrete devices, etc., in which the semiconductor wafer that is cut is cut from approximately the center of the thickness width and each cut surface of each semiconductor wafer is used as an impurity undiffused layer for diffusing new impurities. (Japanese Patent Laid-Open No. 1-293613).
Further, regarding the cutting work of the semiconductor wafer in the above-mentioned manufacturing method or the like, a technique for fixing a contact plate to the peripheral edge of the semiconductor wafer for the purpose of securing the working efficiency and preventing damage to the cutting edge has been previously proposed. (Japanese Patent Laid-Open No. 3-1536).

Conventionally, in the above-mentioned prior proposal of the applicant, as a means for fixing the contact plate to the peripheral edge of the semiconductor wafer, for example, the contact plates are fixed to the upper edge of the semiconductor wafer in parallel with the wafer carrier with an adhesive. Things are going on.

[Problems to be Solved by the Invention] In the above-mentioned conventional means for fixing the contact plate to the peripheral edge of the semiconductor wafer, as shown in FIG. 4, the contact plate P is applied to the semiconductor wafer W before the adhesive C is cured. Is tilted, resulting in insufficient fixing strength and error in dimensional accuracy, and as shown in FIG. 5, the adhesive C flows down to the semiconductor wafer W side and is soiled, resulting in a defective fixing work. There is a problem that

The present invention has been made to solve such a problem, and an object of the present invention is to provide a method for fixing a semiconductor wafer to a contact plate, which has a good finish of the fixing work.

[Means for Solving the Problems] The semiconductor wafer contact plate fixing method of the present invention is a method of fixing the contact plate to the peripheral edge of a semiconductor wafer divided into two by cutting from the center of the thickness width. A semiconductor wafer having an impurity non-diffused layer in which impurities are not diffused in the central portion and an impurity diffusion layer in which impurities are diffused on both sides, and an intermediate plate having a diameter larger than that of the semiconductor wafer are alternately joined and arranged in parallel. After applying pressure from the parallel direction, insert the adhesive-coated contact plate from between the intermediate plates and fix it to the peripheral edge of the semiconductor wafer, or apply the adhesive to the peripheral edge of the semiconductor wafer and apply the adhesive plate from between the intermediate plates. It is characterized by being inserted and fixed.

[Operation] According to the above-mentioned means, the intermediate plate having a diameter larger than that of the semiconductor wafer regulates both the semiconductor wafer and the contact plate in parallel. Since they are fixed to each other, insufficient fixing strength and dimensional accuracy error due to tilting or the like will not occur. Further, since the intermediate plate is pressed against both sides of the semiconductor wafer, even if the adhesive flows out, the intermediate plate prevents the adhesive from flowing down to the semiconductor wafer side (both sides), and the contamination of the semiconductor wafer is prevented. It Therefore, it is possible to achieve an object of providing a method for fixing a semiconductor wafer to a contact plate, which has a good finish of the fixing work.

[Embodiment] An embodiment of a method for fixing a semiconductor wafer to a contact plate according to the present invention will be described below with reference to FIGS. 1 to 3.

In this embodiment, as shown in FIGS. 1 and 2, first, a semiconductor wafer W and an intermediate plate 1 having a diameter larger than that of the semiconductor wafer W are alternately brought into contact with each other, and these are inverted trapezoidal grooves 2 '. Are arranged in parallel with the base 2. The intermediate plate 1 is positioned at both ends of this parallel arrangement. The semiconductor wafer W has a disk shape of silicon single crystal or the like, and has an impurity undiffused layer in which impurities are not diffused in the central portion and an impurity diffusion layer in which impurities are diffused on both sides. . The intermediate plate 1 is made of a material that is not affected by the adhesive C (for example, ethylene tetrafluoride resin), and has a shape that abuts the entire surface of the semiconductor wafer W. The base 2 can be made of an appropriate material, but is preferably made of a material that is not affected by the adhesive C like the intermediate plate 1.

Next, the pressure plates 3 are further arranged in parallel on both side ends of the semiconductor wafer W and the intermediate plate 1 which are arranged in parallel. The pressure plate 3 can be made of an appropriate material, but is preferably the intermediate plate 1.
Like the above, it is formed of a material that is not affected by the adhesive C.

Further, a pressing force is applied in the parallel direction from both sides of the pressure plates 3 arranged in parallel by a clamp or the like. This pressure is applied to the semiconductor wafer W,
The parallel movement of the intermediate plate 1 is maintained and the semiconductor wafer W is moved,
In addition to preventing tilting and displacement, the gap between the semiconductor wafer W and the intermediate plate 1 is reduced to bring them into close contact with each other.

After that, the adhesive C is thickly applied to the periphery of the semiconductor wafer W,
The contact plate P is inserted between the intermediate plates 1 and fixed. As for the peripheral edge of the semiconductor wafer W to which the adhesive C is applied, it is preferable that the upper side in parallel is used, and it is possible to use an orifice. It is also possible to apply the adhesive C to the plate P in advance and fix it. The contact plate P is made of carbon, silicon or the like. The adhesive C may be a heat-resistant resin adhesive such as an epoxy resin, a polyester resin, a polyurethane resin, a polyimide resin, a polyamide resin, or the like, which is made of rubber, depending on the material of the equal plate P and the semiconductor wafer W. System adhesives can also be used.

However, while the adhesive C needs to fix the contact plate P with a strong adhesive force during the cutting of the semiconductor wafer, the contact plate P is fixed by a specific acid solution after the semiconductor wafer is cut into two pieces. Considering that it can be easily peeled off,
It is particularly preferable to use an epoxy resin adhesive.

According to such an embodiment, the intermediate plate 1 having a diameter larger than that of the semiconductor wafer W regulates the semiconductor wafer W in parallel by pressurization, and also regulates the contact plate P inserted between the intermediate plates 1 in parallel. Therefore, the semiconductor wafer W and the plate P move,
It will be fixed by touching in an accurate posture without tilting or slipping. Therefore, in the finish of the fixing work, insufficient fixing strength and dimensional accuracy error due to movement, tilting, displacement, etc. will not occur. Further, since the intermediate plate 1 presses the entire surface of the semiconductor wafer W, the semiconductor wafer W
Is not likely to break. Further, since the intermediate plate 1 is pressed against both sides of the semiconductor wafer W, even if the adhesive C flows out due to an excess or the like, the intermediate plate 1 prevents the adhesive C from flowing down to both sides of the semiconductor wafer W. As a result (see FIG. 3), the semiconductor wafer W is prevented from being contaminated.

[Advantages of the Invention] According to the present invention, since the semiconductor wafer and the contact plate are contacted and fixed in an accurate posture without tilting or the like, insufficient fixing strength or dimensional accuracy error due to tilting or the like does not occur. Further, since the intermediate plates are pressed against both sides of the semiconductor wafer, even if the adhesive flows out when the curing time of the adhesive is long, it is possible to prevent the adhesive from flowing down to the semiconductor wafer and contaminating the semiconductor wafer. Therefore, the finish of the fixing work is good, a predetermined posture can be secured with high accuracy, mass production is possible, and productivity can be improved. Therefore, by using the semiconductor wafer obtained by the present invention, in the cutting work of the semiconductor wafer according to the applicant's previous proposal, precision without breakage such as cracks and chips that are likely to occur around the wafer cutting end and Efficient processing can be performed.

Furthermore, since the parallel and pressurization of the semiconductor wafer through the intermediate plate is used, there is an effect that the existing tools and members can be used at low cost and easily.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a semiconductor wafer contact plate fixing method according to the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is an enlarged view of an essential part of FIG. 1 and FIG. , FIG. 5 is a front view showing the problems of the conventional example. 1 ... Intermediate plate C ... Adhesive P ... This plate W ... Semiconductor wafer

Claims (1)

[Claims] 1. A method of fixing a contact plate to a peripheral edge of a semiconductor wafer which is cut from a center portion of a thickness width and is divided into two; a double-sided surface having an impurity undiffused layer in which impurities are not diffused A semiconductor wafer having an impurity diffusion layer in which impurities are diffused and an intermediate plate having a larger diameter than this semiconductor wafer are alternately joined in parallel and pressed from the parallel direction. A method of fixing a semiconductor wafer to a contact plate, wherein the contact plate is inserted between the plates and fixed to the peripheral edge of the semiconductor wafer, or an adhesive is applied to the peripheral edge of the semiconductor wafer and the contact plate is inserted and fixed between the intermediate plates.