JPS5918856B2 - How to handle wafers - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement in a method for handling a volatilization source wafer (hereinafter referred to as a dopant wafer) and a semiconductor wafer at the stage of diffusing impurities into a semiconductor wafer by a volatilization diffusion method. It is.

Recently, as a method of diffusing impurities into semiconductor wafers...
For example, dopant wafers made of boron nitride (BN) and semiconductor wafers are placed alternately facing each other and inserted into a diffusion furnace at a predetermined temperature, and impurities volatilized from the dopant wafer are diffused into the semiconductor wafer. Diffusion methods are widely used. In this way, in the volatilization diffusion method, at the stage of the diffusion treatment, the semiconductor wafer and the dopant wafer are each taken out from the holder, and these wafers are placed alternately facing each other on the support for diffusion treatment. It is necessary to transfer the semiconductor wafer and the dopant wafer from the support for diffusion treatment to their respective holders after completion of the diffusion treatment.

Conventionally, such work has been carried out by using tweezers to hold and handle the semiconductor wafer and dopant wafer one by one. In addition to the risk of damage or damage, there are also disadvantages of poor workability.
o This invention was made in view of the above-mentioned drawbacks,
By making the outer diameter of the semiconductor wafer and the dopant wafer different, the semiconductor wafer group and the dopant wafer group can be placed and transferred simultaneously by utilizing this difference in outer diameter. It is an object of the present invention to provide a method for handling and handling the above-mentioned wafers with good workability and without fear of contaminating or damaging the surfaces of the above-mentioned wafers.

An embodiment of the method for handling semiconductor wafers and dopant wafers according to the present invention will be described below with reference to FIGS. 1-5.

FIG. 1 is a plan view showing a holder that holds a semiconductor wafer;
FIG. 2 is a cross-sectional view taken along line 1-2 in FIG. 1.

In the figure, 1 is a semiconductor wafer with an outer diameter of about 501φ and 5 is about 200 μm thick, and 2 is a semiconductor wafer holding box that holds the semiconductor wafer 1 with more than half exposed as shown in FIG. 3 holds: - A plurality of semiconductor wafers are provided on both inner walls of the tool 2.
For example, the main surface of the 4.8W11. 2 shows grooves for holding semiconductor wafers 1 so as to be aligned and facing each other with an interval t of about 100 mm.

FIG. 3 is a plan view showing a holder that holds a dopant wafer. In the figure, 1a has an outer diameter of 5711φ, for example.
The dopant wafer has a thickness of about 1 nm, and the outer diameter of the dopant wafer 1a is set to be larger than the outer diameter of the semiconductor wafer 1 shown in FIG.

2a is a dopant wafer holder 3a that holds the dopant wafer 1a similarly to the semiconductor wafer holder 2 in FIG.
4 is similar to the groove 3 of the semiconductor wafer holder 2 in FIG.
．． These grooves are provided on both inner walls of the dopant wafer holder 2a at an interval t of about 8 m1 and hold the dopant wafer 1a.

Since the depth of the groove 3a is set so that the dopant wafer 1a is about 7u larger than the semiconductor wafer 1, the depth of the groove 3a is about 3.511 mm deeper than the groove 3 in FIG. Further, since the cross-sectional shape of the dopant wafer holder 2a is similar to the cross-sectional shape of the semiconductor wafer holder 2 shown in FIG. 2, illustration of the cross-sectional shape is omitted. Fig. 4a is a partially enlarged plan view showing a part of the wafer support for diffusion processing used during volatilization and diffusion processing, and Fig. 4b is Fig. 4 AONB.
- It is a longitudinal cross-sectional view along the NB line.

In the figure, 2b is made of silicon carbide SlC, for example, and the semiconductor wafer 1 in FIG. 1 and the dopant wafer 1a in FIG.
This is a wafer support stand for diffusion processing used during volatilization and diffusion processing, in which wafers are aligned and supported alternately facing each other.

On both inner walls of this wafer support stand 2b for diffusion processing, there are grooves 3b for holding the semiconductor wafer 1 corresponding to the grooves 3 in FIG. 1, and grooves 3b for holding the dopant wafer 1 corresponding to the grooves 3a in FIG.
Grooves 3b2 for holding the grooves 3b2 and 3b2 are provided alternately. Also,
Since the cross-sectional shape of the diffusion processing wafer support stand 2b is similar to the cross-sectional shape of the semiconductor wafer holder 2 shown in FIG. 2, illustration of the cross-sectional shape is omitted. FIG. 5 is a perspective view showing a gripping tool used for handling a wafer for volatilization and diffusion.

In the figure, reference numeral 4 denotes a gripping tool, and the gripping tool 4 is composed of two elastic plates 5 made of, for example, perylium copper, with one end facing each other and the other end attached to a fixed plate 6.

A buffer plate 7 made of a flexible member is attached to the opposing surface of the elastic plate 5. By using the gripping tool 4 configured in this manner, the end surfaces of a plurality of semiconductor wafers 1 inserted into the grooves 3 of the semiconductor wafer holder 2 shown in FIG. It can be extracted from.

Similarly, the end faces of a plurality of dopant 9-pad wafers 1a can be simultaneously pinched and removed from the dopant wafer holder 2a shown in FIG. Next, before the volatilization and diffusion treatment, a plurality of semiconductor wafers 1 held in a semiconductor wafer holder 2 and a plurality of dopant wafer wafers 1a held in a dopant wafer holder 2a are subjected to the diffusion process shown in FIG. The step of transferring the processing wafer to the support stand 2b will be explained one by one.

First, a plurality of semiconductor wafers 1 having an outer diameter smaller than the dopant wafer 1a are simultaneously extracted from the semiconductor wafer holder 21 using the gripping tool 4.

Next, the extracted semiconductor wafer 1 is inserted as it is into the groove 3b of the wafer support base 2b for diffusion processing.
At this time, since the interval between the grooves 3 of the semiconductor wafer holder 2 holding the semiconductor wafer 1 and the interval between the grooves 3b1 are the same, the semiconductor wafer 1 can be easily inserted into the groove 3b1. Next, as in the case of the semiconductor wafer 1, a plurality of dopant wafers 1a are extracted from the dopant wafer holder 2a using the gripping tool 4, and inserted into the groove portion 3b2 of the wafer support base 2b for diffusion processing. At that time, the distance between the grooves 3a of the dopant wafer holder 2a and the distance between the grooves 3b2 are the same, and the outer diameter of the dopant wafer 1a is larger than that of the semiconductor wafer 1, so that the semiconductor wafer 1 undergoes the diffusion process. Groove 3b of wafer support stand 2b for
1, the dopant wafer 1a can be inserted. After the volatilization and diffusion processing, the semiconductor wafer 1 and dopant wafer 1a inserted into the wafer support 2b for diffusion processing are transferred from the wafer support 2b for diffusion processing to the semiconductor wafer holder 2 and the dopant wafer holder 2a, respectively. Even in the changing stage, the dopant wafer 1a is first pinched and removed from the diffusion treatment wafer support 2b using the gripping tool 4 by taking advantage of the difference in the outer diameter of the semiconductor wafer 1 and the outer diameter of the dopant wafer 1a. It can be transferred to the wafer holder 2a.

Subsequently, the semiconductor wafer 1 can also be transferred to the semiconductor wafer holder 2 in the same manner. In the above embodiment, the semiconductor wafers 1 and the dopant wafers 1a are arranged alternately, but they do not necessarily need to be arranged alternately, and they may be arranged in a predetermined order.

As explained above, according to the method according to the present invention,
The outer diameter of the semiconductor wafer is different from the outer diameter of the wafer for volatilization diffusion source, and the main surface of the semiconductor wafer and the main surface of the wafer for volatilization diffusion source are set so as to face each other at a predetermined interval. For each semiconductor wafer group or volatilization source wafer group out of the wafer rows arranged in order, a wafer belonging to the group is placed on the end face, and a buffer plate made of a flexible member is attached to the opposing face. Since the wafers are simultaneously pinched and handled using a tool, there is no contamination or damage to the surfaces of the wafers, compared to the conventional method of handling the wafers one by one using tweezers or the like. Workability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a semiconductor wafer holder used in an embodiment of the method for handling semiconductor wafers and dopant wafers according to the present invention, FIG. 2 is a cross-sectional view taken along line -H in FIG. 1, and FIG. The figure is a plan view showing a dopant wafer holder used in the above embodiment, FIG. FIG. 4a is a vertical sectional view taken along the line NB--NB, and FIG. 5 is a perspective view showing the gripping tool used in the above embodiment. In the figure, 1 is a semiconductor wafer, 1a is a dopant wafer (a wafer for volatilization and diffusion source), 2 is a semiconductor wafer holder, 2a is a dopant wafer holding unit, 2b is a wafer for diffusion processing, a support stand, 3, 3a , 3b1 and 3b2 are grooves, 4 is a gripping tool, 5 is an elastic plate, 6 is a fixing plate, and 7 is a buffer plate.

Claims (1)

[Claims] 1. In a method of arranging a semiconductor wafer and a wafer for a volatilization diffusion source to face each other in a predetermined order and volatilizing and diffusing impurities to the semiconductor wafer, the outer diameter of the semiconductor wafer is different from the outer diameter of the wafer for a volatilization diffusion source. At the same time, among the wafer rows arranged in a predetermined order such that the main surface of the semiconductor wafer and the main surface of the wafer for volatilization and diffusion source face each other with a predetermined interval, a group of semiconductor wafers or a wafer for volatilization and diffusion source are arranged in a predetermined order. A method for handling wafers, comprising simultaneously holding and handling wafers belonging to each group of wafers using a gripping tool having a buffer plate made of a flexible member attached to an opposing surface of each wafer group.