JPH0741397A - Device for heat treatment of semiconductor - Google Patents

Abstract

PURPOSE:To provide a heat treating device for semiconductors in which a semiconductor crystal can be subjected to multistage heat treatment at a high temp., a block sample can be heat treated, and rapid heating and rapid cooling can be done. CONSTITUTION:This heat treating device 1 for semiconductors is equipped with a silicon carbide heater 5 as a heat generator and a silicon carbide tube 3 as a reaction tube. In this device, the max. temp. for heat treatment of a sample is >=1400 deg.C with >=50mm soaking length, the controllable cooling rate is 0-30 deg.C/min in 1200-1400 deg.C temp. range and 0-25 deg.C/min in 100-1200 deg.C temp. range, and the controllable temp. rising rate is 0-15 deg.C/min in 1200-1400 deg.C temp. range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor heat treatment apparatus capable of performing a multi-stage heat treatment of a semiconductor crystal at a high temperature, heat treatment of a block-shaped sample, and rapid heating and cooling.

[0002]

2. Description of the Related Art In the manufacturing process of devices such as LSI, heat treatment of semiconductor crystals is indispensable. Therefore, the semiconductor heat treatment apparatus has been frequently used since before, and the general performance of the semiconductor heat treatment apparatus is that it has a resistance metal wire as a heating element, a quartz tube as a reaction tube, and a maximum temperature of 1200 ° C.
And the soaking length was several hundred mm. However, it does not have the capability of rapid heating and rapid cooling for the purpose of the device, and the controllable cooling rate is from 1000 ° C to 12 ° C.
In the temperature range of 00 ° C., 10 ° C./min or less, and the controllable heating rate was 10 ° C./min or less in the same temperature range.

Recently, with the progress of silicon wafers with a buried insulating oxide layer, silicon carbide is used as a heating element, and a silicon carbide tube is used as a reaction tube. The maximum temperature is 1350 ° C. and the soaking length is several. A semiconductor heat treatment apparatus having a performance of up to 100 mm was manufactured. However, the conventional silicon carbide pipe is weakly broken by rapid heating and rapid cooling, has a heat storage structure to prevent heat loss at high temperatures, and requires rapid heating and rapid cooling for the purpose of the device. Therefore, the allowable cooling degree is 1200
The heating rate was 5 ° C./min or less from 0 ° C. to 1400 ° C. and the allowable heating rate was 5 ° C./min or less in the same temperature range.

With the progress of wafer quality improvement technology,
The need for rapid heating and rapid cooling has increased, and a heat treatment apparatus using a lamp heating system has been created. The maximum operating temperature of the device is 1350 ° C or higher, and the controllable cooling rate is 120
100 ° C / min or more in a temperature range of 0 ° C to 1400 ° C, and a controllable cooling rate is 10 ° C in a temperature range of 1200 ° C to 1400 ° C.
C / sec or more. However, since the soaking length can be only a few mm, only the heat treatment for each wafer can be performed.

As described above, there is no semiconductor heat treatment apparatus capable of performing multi-stage heat treatment of a semiconductor crystal at high temperature and heat treatment of a block-shaped sample, and performing rapid heating and rapid cooling.

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention provides a semiconductor heat treatment apparatus capable of performing multi-step heat treatment of a semiconductor crystal at a high temperature, heat treatment of a block-shaped sample, and rapid heating and cooling. The purpose is to

[0007]

The above object is to have a silicon carbide heater as a heating element and a silicon carbide tube as a reaction tube, and the maximum temperature for heat-treating a test object is 1400 ° C.
Above, the soaking length is 50 mm or more, and the controllable cooling rate is 0 to 30 in the temperature range of 1200 ° C to 1400 ° C.
0 to 25 in the temperature range of 1000 ° C to 1200 ° C at ℃ / min.
℃ / min, controllable heating rate is 1200 ℃ ~ 14
It can be realized by a semiconductor heat treatment apparatus having a temperature range of 00 ° C. of 0 to 15 ° C./min.

[0008]

[Function] As a heating element of the heat treatment apparatus, 300 ° C to 12 ° C
In the temperature range of 00 ° C, a metal resistance wire is used and 1200
Silicon carbide is used at temperatures between 1 ° C and 1600 ° C. Since the heat treatment atmosphere is required to be kept highly clean in the semiconductor heat treatment apparatus, high-purity quartz is used as the reaction tube at 1150 ° C. or lower, and high-purity silicon carbide impregnated with silicon is used at 1200 ° C. to 1350 ° C. . However, 1400 ° C
When used above, the high-purity silicon carbide material impregnated with silicon cannot be used because the silicon softens, and since the high-purity silicon carbide itself is dense, it is vulnerable to heat shock and is subject to rapid heating and rapid heating. It will be destroyed by cooling. On the other hand, porous high-purity silicon carbide is sintered under normal pressure to form a tube shape, and a high-purity silicon carbide CVD film is further deposited on the surface to prevent pores on the surface and withstand high temperatures of 1400 ° C or higher. In addition, a reaction tube that is resistant to heat shock and capable of heat treatment in a highly clean atmosphere can be obtained.

Further, in the chamber surrounding the heat generating element, the heat insulating element is not densely packed around the heat generating element, but the heat insulating material is arranged only on the inner wall of the chamber to create a space as large as possible around the heat generating element. By 1200 ℃
0 ~ 30 ℃ / min and 1000 ℃ in the temperature range of ~ 1400 ℃
A controllable cooling rate of 0 to 25 ° C / min can be created in the temperature range of to 1200 ° C.

Therefore, a silicon carbide rod is used as a heating element, and an atmospheric pressure sintered porous high-purity silicon carbide tube having an ultrahigh-purity silicon carbide CVD film deposited on the surface is used as a reaction tube, and the inner wall of the chamber surrounding the heating element is used. By installing a heat insulating material only in the space and creating a space as large as possible around the heating element, the maximum temperature is 1400 ° C or higher, and the controllable cooling rate is 0 to 30 ° C in the temperature range of 1200 ° C to 1400 ° C. / Min and 0 to 25 ° C / min in the temperature range of 1000 ° C to 1200 ° C. 50m by arranging silicon carbide rods in parallel vertically
It is possible to create a soaking length of m or more, and by increasing the number of silicon carbide rods, the controllable heating rate is 120.
It becomes 0 to 15 ° C / min in the temperature range of 0 ° C to 1400 ° C. With the semiconductor heat treatment apparatus thus manufactured, semiconductor crystals can be heat-treated in multiple stages at a high temperature, and a block-shaped sample can be heat-treated, so that rapid heating and rapid cooling between temperatures can be performed.

[0011]

EXAMPLES The present invention will be described below with reference to the examples shown in FIG. 1, but it goes without saying that the present invention is not limited by the description of these examples. The semiconductor heat treatment apparatus 1 of the present invention comprises a heater chamber 2 in which a heating element is housed, and a reaction tube 3 which penetrates the center of the heater chamber to the left and right. A heat treatment is performed by putting the test article in the reaction tube 3 and moving it to the center of the furnace.
The outer shape of the heat treatment apparatus 1 is 640 mm in width and 500 m in depth.
m and height 600 mm. The inner wall of the heater chamber 2 is covered with a heat insulating material 4 made of alumina fiber to block heat exchange with the outside. However, the heat insulating material 4 has about 2 inner walls.
It only covers two layers with a thickness of 5 mm, and there is a large space in the chamber. In the space inside the heater chamber, six heating elements 5 made of silicon carbide are arranged vertically in a row in the reaction tube 3 at intervals of about 80 mm.
The heating element has a cylindrical shape with a diameter of 10 mm and a length of 450 mm. Table 1 shows the temperature characteristics of this semiconductor heat treatment apparatus. FIG. 3 shows a heat treatment pattern of the apparatus of the present invention. It is possible to heat-treat a semiconductor crystal in multiple stages at a high temperature and heat a block-shaped sample, and to perform rapid heating and rapid cooling between respective temperatures.

Comparative Example Next, a comparative example shown in FIG. 2 will be described. The conventional semiconductor heat treatment apparatus 11 is composed of a heater chamber 12 in which a heating element is housed and a reaction tube 13 which penetrates the center of the chamber to the left and right. The inside of the heater chamber is almost entirely filled with a heat insulating material 14 to prevent heat from leaking to the outside.
In the gap between the heat insulating material 14 and the reaction tube 13 in the heater chamber, a metal resistance wire heater 15 is provided so as to surround the reaction tube 13.
Is spirally wound. The temperature characteristics of this semiconductor heat treatment apparatus are shown in Table 1 together with Example 1. FIG. 4 shows a heat treatment pattern of Comparative Example 1. Block-shaped samples can be heat-treated, but high-temperature heat treatment cannot be performed, and rapid heating and rapid cooling between respective temperatures are also impossible.

[0013]

[Table 1]

[0014]

According to the present invention, a semiconductor crystal can be heat-treated in multiple stages at a high temperature and a block-shaped sample can be heat-treated.
Suitable for high-quality silicon single crystal development because rapid heating and cooling are possible.

[Brief description of drawings]

FIG. 1 is a drawing showing a cross-sectional view of Embodiment 1 of the present invention,

FIG. 2 is a drawing showing a cross-sectional view of Comparative Example 1 which is a conventional technique;

FIG. 3 is a graph showing an example of a heat treatment pattern that can be executed in Example 1;

FIG. 4 is a graph showing an example of a heat treatment pattern that can be executed in Comparative Example 1.

[Explanation of symbols]

1 ... Semiconductor heat treatment apparatus, 2 ... Heater chamber, 3
... Reaction tube (pressureless sintered porous high-purity silicon carbide tube having ultra-high-purity silicon carbide CVD film deposited on the surface), 4 ... Insulating material,
5 ... Heating element (heater made of silicon carbide), 11 ...
Semiconductor heat treatment apparatus, 12 ... Heater chamber, 13 ...
Reaction tube (quartz), 14 ... Insulating material, 15 ... Heating element (resistive metal wire).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tsuneo Nakatsune, 3434 Shimada, Hitsu-shi, Yamaguchi Yamada Prefecture, Komatsu Ltd. (72) Kiyoshi Kojima, 3434, Shimada, Hikari-shi, Yamaguchi Nittetsu Den Child Co., Ltd.

Claims (2)

[Claims] 1. An apparatus for heat-treating a semiconductor, wherein a maximum temperature for heat-treating a test object is 1400 ° C. or higher, a soaking length is 50 mm or more, and a controllable cooling rate is 1200 ° C. to 1400 ° C. 0 to 30 ° C./min in the temperature range of 0 to 25 ° C./min in the temperature range of 1000 ° C. to 1200 ° C., and the controllable heating rate is 0 to 15 ° C./min in the temperature range of 1200 ° C. to 1400 ° C. A semiconductor heat treatment apparatus characterized by: 2. The semiconductor heat treatment apparatus according to claim 1, further comprising a silicon carbide heater as a heating element and a silicon carbide tube as a reaction tube.