JPH04196521A - Fixing method for semiconductor substrate - Google Patents

Abstract

PURPOSE:To obtain a semiconductor substrate fixing method wherein working is enabled simply in a short time, and possibility of contaminating a semiconductor substrate is little, by heating a semiconductor substrate on a substrate holder, fusing metal for fixing the substrate which metal is formed on the rear of the substrate, and hardening said metal by cooling. CONSTITUTION:A substrate holder 11 is heated from the rear by a heater 14. Metal 12 for fixing a substrate is indirectly heated by the heat from the substrate holder 11, and fused on the substrate holder. By keeping this state for several minutes, the fused metal is made compatible with the substrate and the substrate holder. After that, the substrate holder 11 is detached from the heater 14, and the substrate holder 11, the metal 12 and the substrate 13 are cooled. Thus the metal 12 for fixing a substrate is hardened, and the semiconductor substrate 13 is fixed on the substrate holder 11. By forming the metal 12 for fixing a substrate on the rear of the semiconductor substrate 13 in this manner, the semiconductor substrate 13 can be easily fixed on the substrate holder 11, without contaminating the surface.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for fixing a semiconductor substrate to a substrate holder.

Conventional technology In conventional crystal growth methods, especially molecular beam epitaxy, in order to fix a semiconductor substrate to a substrate holder, a method of using a soft substrate fixing metal such as indium with a low melting point on the substrate holder is often used. There is. In this method, a metal for fixing a substrate is heated and melted, a semiconductor substrate is moved on top of the metal, and the semiconductor substrate is sufficiently blended with the substrate holder and the back surface of the semiconductor substrate, and then the metal is cooled to fix the semiconductor substrate. At this time, all metal parts other than the metal for fixing the substrate at the bottom of the semiconductor substrate are removed to prevent them from affecting the grown crystal.

Recently, a method of fixing a semiconductor substrate from the surface side of the semiconductor substrate using a stopper made of molybdenum or the like has also been widely used.

Problems to be Solved by the Invention However, when a semiconductor substrate is fixed using a substrate identification metal, it is necessary to sufficiently blend the back surface of the semiconductor substrate or the substrate holder with the substrate fixing metal. If this operation is incomplete, the state of adhesion of the metal for fixing the substrate will be uneven, resulting in in-plane distribution of the substrate temperature during crystal growth, which will reduce the in-plane uniformity of the grown crystal. In addition, when performing the work of blending the back side of the semiconductor substrate with the board fixing metal, the semiconductor substrate is moved over the molten board fixing metal, so if the work is not done carefully, the surface of the single conductor board will be rubbed with the board fixing metal. It will become contaminated.

As described above, the conventional method of fixing a semiconductor substrate using a substrate fixing metal requires the skill of the operator to achieve uniform crystal growth, and there is a possibility that the semiconductor substrate may be contaminated by the substrate fixing metal. There was a problem.

On the other hand, with the method of fixing the semiconductor substrate using a clasp, although there is no contamination of the semiconductor substrate, the temperature of the substrate changes from the set value near the clasp due to heat conduction from the clasp, and there is no problem in that area. The problem was that crystal growth could not be achieved.

The present invention solves these conventional problems and provides a method for fixing a semiconductor substrate, which can be easily carried out in a short time and is less likely to contaminate the semiconductor substrate.

Means for Solving the Problem In order to achieve this object, the semiconductor substrate fixing method of the present invention uses a semiconductor substrate with a substrate fixing metal provided on the back side of the semiconductor substrate in advance, and heats this semiconductor substrate on a substrate holder. The substrate fixing metal on the back side of the semiconductor substrate is melted and then cooled to solidify the substrate fixing metal and fix the semiconductor substrate on the substrate holder.

Function: In the method for fixing a semiconductor substrate of the present invention, a metal for fixing the substrate is provided on the back side of the semiconductor substrate in advance, and there is no need to blend the substrate and the substrate holder with the metal for fixing the substrate.
The semiconductor substrate and the substrate holder can be easily and evenly fixed with the substrate fixing metal. In addition, the semiconductor substrate fixing method is extremely simple and does not require any skill in manual labor, and the possibility of contaminating the semiconductor substrate surface during the operation can be reduced.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing a method of fixing a semiconductor substrate to a substrate holder in a first embodiment of the present invention. In FIG. 1, 11 is a substrate holder, 12 is a metal for fixing the substrate,
13 is a semiconductor substrate, and 14 is a heater. Heater 1
A substrate holder 11 is placed on top of the substrate holder 4, and a semiconductor substrate 13 having a substrate fixing metal 12 deposited on its back surface is further placed on top of the substrate holder 11.

The procedure of the first embodiment configured as described above will be explained below.

The substrate holder 11 is heated from the back side by the heater 14, and the substrate fixing metal 12 is indirectly heated by the heat from the substrate holder 11 and melted on the substrate holder. By maintaining this state for several minutes, the molten substrate fixing metal can be blended with the substrate and substrate holder. After that, the substrate holder 11 is removed from the heater 14, and the substrate boulder 11, the substrate fixing metal 12, and the semiconductor substrate 13 are removed.
The semiconductor substrate 1 is cooled and the substrate fixing metal 12 is solidified.
3 is fixed to the substrate holder 11.

As described above, according to this embodiment, by providing the substrate fixing metal 12 on the back surface of the semiconductor substrate 13, the semiconductor substrate
3 can be easily fixed to the substrate holder 11 without contaminating the surface.

A second embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a method of fixing a semiconductor substrate to a substrate holder according to a second embodiment. In the same figure, 21 is a substrate holder, 22 is a semiconductor substrate, and 23 is a substrate fixing metal, which is the same as the structure shown in FIG. It is placed on 21. The difference from the configuration shown in FIG. 1 is that a nitrogen gun 24, nitrogen 25, and nitrogen heating heater 26 are provided. With this configuration, the nitrogen 25 emitted from the nitrogen gun 24 is heated to a temperature of 200° C. or more by the nitrogen heating heater 26 which is heated with electricity.

Regarding the second embodiment configured as above, a method for fixing the substrate will be described below.

2. The nitrogen 25 emitted from the nitrogen gun 24 is heated by the nitrogen heating heater 35 so that the temperature becomes 200° C. or higher. By blowing this heated nitrogen 25 onto the semiconductor substrate 22, the substrate holder 21, the semiconductor substrate 22, and the substrate fixing metal 23 are heated. The semiconductor substrate 22 can be fixed by continuing heating until the substrate fixing metal 23 melts and is sufficiently compatible with the substrate holder 21, and then cooling naturally to solidify the substrate fixing metal 23.

In this case, the cooling of the metal 22 for fixing the substrate is performed by natural cooling, but it goes without saying that cooling may be performed forcibly using a gas such as nitrogen in order to shorten the cooling time. At this time, if the electricity is turned off to the substrate heating heater 26 and the heating of the nitrogen 24 is stopped, the semiconductor substrate 22 is cooled by the nitrogen 24, so that the semiconductor substrate 22 is heated and
Cooling can be performed continuously, increasing work efficiency.

Effects of the Invention As described above, the semiconductor substrate fixing method of the present invention provides the substrate fixing metal on the back side of the semiconductor substrate, and by heating with a heater, the substrate fixing metal is evenly applied to the semiconductor substrate back side. It is extremely useful in practice because it can be attached to a substrate holder and a semiconductor substrate can be easily fixed to a substrate holder in a short time without contaminating the surface.

[Brief explanation of the drawing]

1 and 2 are conceptual side views showing the semiconductor substrate fixing method in the first and second embodiments of the present invention. 11...Substrate holder, 12 Semiconductor substrate, 13
Metal for fixing the substrate, 14...Heater, 21.Substrate holder, 22...Semiconductor substrate, 23.Metal for fixing the substrate, 2
4. Nitrogen gun, 26... Nitrogen heating heater.

Claims (4)

[Claims] (1) When fixing a semiconductor substrate to a substrate holder, use a semiconductor substrate with a thin film of substrate fixing metal provided on the back side of the semiconductor substrate in advance, and heat it on the substrate holder to melt the substrate fixing metal. A method for fixing a semiconductor substrate, comprising cooling the semiconductor substrate and fixing the semiconductor substrate on a substrate holder. (2) The semiconductor substrate fixing method according to claim 1, wherein the thin film-like substrate fixing metal provided on the back surface of the semiconductor substrate has a thickness of 0.1 to 2 mm. (3) The semiconductor substrate fixing method according to claim 1, characterized in that indium, which is a low melting point metal, is used as the substrate fixing metal. (4) The method for fixing a semiconductor substrate according to claim 1, characterized in that the method for heating the metal for fixing the substrate includes using heated gas and blowing the gas from the surface of the semiconductor substrate to melt the metal for fixing the substrate.