JPH02139919A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent nonuniformity of heating and development of crystal defects due to heat distortion by providing a wafer with wafer surfaces approximately parallel each other inside an inner side tube having inner surfaces which are approximately parallel each other and by inserting the inner side tube into an outer side tube which is heated in advance. CONSTITUTION:Inner surfaces 7a of an inner side quartz tube 7 are approximately parallel each other, and an inner surface 7a and a wafer surface 30 of an Si wafer 3 are also parallel. Although the Si wafer 3 is heated through the inner side quartz 7, the wafer surface 3a of the Si wafer 3 is approximately parallel to the inner surface 7a of the inner side quartz tube 7; therefore, heat flows at right angles to the wafer surface 3a and the wafer surface 3a is uniformly heated. Although an outer side quartz tube 1 is heated in advance by a furnace body 4, the Si wafer 3 prevents development of heat distortion due to rapid heating of a heat capacity of the inner side quartz tube 7.

Description

[Detailed Description of the Invention] [Industrial Application] The invention of Part B relates to a semiconductor device manufacturing apparatus that performs heat treatment on a semiconductor sea urchin in a semiconductor device manufacturing process.

[Conventional technology]

FIGS. 4(a) and 4(b) are a front sectional view and a side view showing a conventional semiconductor device manufacturing apparatus. In FIG. 4, 1 is a quartz tube (referred to as the outer quartz tube in the embodiment described above), 2 is a quartz boat inserted into the quartz tube 1, and 3 is a Si wafer juxtaposed on this quartz boat 2. , 4
is a furnace body for heating the Si wafer 3 through the quartz tube 1, 5 is a gas supply port to the quartz tube 1, and 6 is an inlet for the quartz boat 2 provided in the quartz tube 1. be.

Next, the operation will be explained.

The quartz bowl 1-2 is a jig for holding the Si wafer 3,
The Si wafer 3 needs to be heated to a high temperature of around 1000°C for impurity diffusion, oxidation, CVD, annealing, etc.
For this purpose, the quartz tube 1 is heated in advance by the furnace body 4, and the Si wafer 3 held in the quartz boat 2 is inserted into the quartz tube 1 through the insertion port 6. From the gas supply port 5, N, O, and other gases are introduced as necessary to maintain the S1 sea urchin 8 3 in a constant atmosphere.

[Problem to be solved by the invention]

Since the conventional semiconductor device manufacturing apparatus is configured as described above, there is a problem in that the heating gas for the Si wafer 3 is unrestricted τ. That is, since the heating progresses from the periphery of the Si wafer 3 toward the center, a temperature gradient occurs inside the Si wafer 3, which causes internal distortion in the Si wafer 3 and crystal defects. . In addition, Sl wafer 3
When inserted through the insertion port 6 of the quartz tube 1, it is suddenly exposed from a low temperature to a high temperature, so that temperature non-uniformity occurs inside the S1 wafer 3 at this time as well, resulting in crystal defects.

Because of these defects, conventional semiconductor device manufacturing apparatuses have problems that cannot be put to practical use with wafers of a certain or larger area.

Furthermore, in the conventional semiconductor device manufacturing apparatus, since the gas supply port 5 is located at the end of the quartz tube 1, the Si
Since a large number of wafers 3 are installed in series, fresh gas cannot be uniformly applied to the wafer surface. Therefore, especially when the supplied gas is a reactive gas, problems may arise in uniformly supplying impurities to the wafer surface or in forming an oxide film.

This invention was made to solve the above-mentioned problems, and by uniformly heating the semiconductor wafer, it is possible to produce semiconductors that do not cause defects such as crystal defects even in large-area semiconductor wafers. The purpose is to provide equipment for manufacturing equipment.

[Means to solve the problem]

The semiconductor device manufacturing apparatus according to the present invention is placed on a boat and is made of a heat-resistant material and has inner surfaces that are substantially parallel to each other. It is provided with an outer tube made of a material, and a gas inlet and a gas outlet so as to be inserted into the inner tube and to supply gas parallel to the wafer surface of the semiconductor wafer.

[Effect]

In this invention, the semiconductor wafer placed on a boat is inserted into an inner tube, and this inner tube is inserted into an outer tube to perform heat treatment, so that the semiconductor wafer is not heated rapidly. This prevents uneven heating on the wafer surface due to rapid heating, and prevents crystal defects due to thermal distortion.

Furthermore, since the gas flow is uniform over the wafer surface, impurities can be uniformly supplied to the wafer surface.

〔Example〕

FIG. 1(b) is a front sectional view and a side sectional view of a semiconductor device manufacturing apparatus showing an embodiment of the present invention. In this figure, the same reference numerals as in FIG. 4 indicate the same things, Reference numeral 7 denotes an inner quartz tube pushed into the outer quartz tube 1, and the inner surfaces 7a of the inner quartz tube 7 are substantially parallel to each other. 3a is also almost parallel.

Next, the operation will be explained.

The silicon tube 3 is heated through the entire inner quartz tube 7,
The wafer surface 3a of the Si wafer 3 is the inner surface 7 of the inner quartz tube 7.
Since the heat flow is substantially parallel to a, the heat flow flows in a direction perpendicular to the wafer surface 3a, so that the wafer surface 3a is uniformly heated. The quartz boat 2 is inserted into the inner quartz tube 7;
By holding the wafer 3, the Si wafer 3 is inserted into the inner quartz w7. The outer quartz tube 1 is generally preheated by the furnace body 4, and the inner quartz tube 7 on which the Si wafer 3 is installed is inserted into the preheated outer quartz w1. At this time, the Si wafer 3 is not heated rapidly due to the heat capacity of the outer quartz tube 1. Therefore, it is possible to prevent thermal distortion caused by rapid heating.
Generation of crystal defects and deformation of the Si wafer 3 due to thermal strain can be prevented. Furthermore, even when the inner quartz tube 7 is pulled out from the outer quartz tube 1, the Si wafer 3 is not cooled rapidly due to the heat capacity of the inner quartz tube 7. Therefore, it has the same effect as described above. In this way, the Si wafer 3 is heated and cooled uniformly in terms of location and smoothly in terms of time.

FIGS. 2(a) and 2(b) are a front sectional view and a side sectional view showing another embodiment of the present invention. In this figure, the first
The same reference numerals as in the figure indicate the same things, and 8 is the quartz boat 2.
The inner quartz tube is inserted into a rectangular shape. Reference numeral 11 designates an outer quartz tube formed in the same shape as the inner quartz tube 8, into which the inner quartz tube 8 is inserted.

The inner surfaces 8a of the inner p-quartz tube 8 are substantially parallel to each other, and the inner surfaces 8a and the wafer surface 3a of the Si wafer 3 are also substantially parallel. Further, in this embodiment, the inner surfaces 11a of the outer quartz tubes 11 are also substantially parallel to each other, and the inner surfaces 11a, the inner surfaces 8a of the inner quartz tubes 8, and the wafer surface 3a are also substantially parallel. 3a is not only substantially parallel to the inner surface 8a of the inner quartz tube 8, but also substantially parallel to the inner surface tfa of the outer quartz tube 11, so that the heat flow is more perpendicular to the wafer surface 3a. (The wafer surface 3a is heated more uniformly than in the embodiment shown in FIG. 1.)

FIGS. 3(a) and 3(b) are a front sectional view and a side sectional view showing still another embodiment of the present invention.

In this figure, the same reference numerals as in FIG. 1, FIG. 2, and FIG.
is inserted. The inner quartz tube 9 has a gas inlet 9a and a gas outlet 9b formed at required locations on its outer peripheral surface, the gas inlet 9a has a gas inlet 5a, and the gas outlet 9b has a gas outlet 5b. Each is provided. A small gas supply hole 10b consisting of a large number of small holes for ejecting gas is formed in the inner wall 10a on the gas introduction side of the inner quartz tube 9, and a small gas discharge hole 10d is formed in the inner wall 10c on the gas introduction side.
are formed respectively. The inner wall surface of the inner wall 10a and the inner wall surface of the inner wall 10b are formed to face each other, so that the gas flow is uniform with respect to the Sl wafer 3. In addition, insert 1 of the quartz bow)-2 of the inner quartz tube 9.
6 is fitted with a cap 13 for sealing the inside of the pipe to prevent external atmosphere other than the supply gas from entering the pipe, and a flexible pipe 14 is connected to the gas inlet 5a. By using this flexible piping 14, the inner quartz f
It becomes easy to put in and take out f9. Note that as long as the structure is such that external atmosphere does not mix into the inner quartz tube 9, the inner wall 1
0a and 10c do not need to be integral with the outer quartz tube 12.

In the above embodiment, the case where the Si wafer 3 is used as the semiconductor wafer has been described, but other semiconductor wafers such as Ge and GaAs may also be used.

In addition, in each of the above embodiments, a quartz tube was explained, but
The tube may be made of other heat-resistant materials such as poly-Si or graphite.

〔Effect of the invention〕

As explained above, this invention consists of an inner tube made of a heat-resistant material with inner surfaces substantially parallel to each other and placed on a boat into which a semiconductor wafer is inserted, and a heat-resistant material into which this inner tube is inserted. An outer tube is inserted into the inner tube, and a gas inlet and a gas outlet are provided so that the gas is supplied parallel to the wafer surface of the semiconductor wafer.
The wafer can be heated uniformly, and therefore crystal defects and deformation of the wafer due to heating can be prevented.

In addition, when inserting the tube with the wafer installed into a further heated tube, the gas flow can be made uniform by arranging the gas supply and discharge ports to face each other.
The wafer surface can be uniformly subjected to reaction treatment.

[Brief explanation of the drawing]

1(a) and 1(b) are a front sectional view and a side sectional view of a semiconductor device manufacturing apparatus showing one embodiment of the present invention, and FIGS. 2(a) and 2(b) are another embodiment of the present invention. FIG. 3(a) is a front sectional view and a side sectional view showing an example. (b) is a front sectional view and a side sectional view showing still another embodiment of the present invention, and FIGS. 4(a) and 4(b) are a front sectional view and a side view showing a conventional semiconductor device manufacturing equipment building. . In the figure, 1, 11, 12 are outer quartz tubes, 2 is a quartz boat, 3 is a Si wafer, 3a is a wafer surface, 4 is a furnace body,
5 is a gas supply port, 5a is a gas inlet, 5b is a gas outlet, 6 is a quartz tube insertion port, 7°8.9 is an inner quartz tube, 7
a, 8a, 11 a is an inner surface, 9a is a gas inlet, 9b is a gas outlet, 10a, 10c are inner walls, 10b is a small hole for gas supply, and 10d is a small hole for gas discharge. Note that the same reference numerals in each figure indicate the same or equivalent parts.

Claims (1)

[Claims] A semiconductor device manufacturing apparatus that heat-processes semiconductor wafers placed on a boat includes an inner tube made of a heat-resistant material and having inner surfaces substantially parallel to each other, into which the semiconductor wafers placed on the boat are inserted; An outer tube made of a heat-resistant material into which the inner tube is inserted, and a gas inlet and a gas outlet so as to be inserted into the inner tube and to supply gas parallel to the wafer surface of the semiconductor wafer. A semiconductor device manufacturing apparatus characterized by: