JPH05347257A - Vacuum vapor growth device - Google Patents

Abstract

PURPOSE:To enable a vapor growth film to be formed uniform in thickness without providing a temperature gradient in a vacuum vapor growth device even if the growth device has a long growth zone. CONSTITUTION:A vacuum vapor growth device is equipped with a quartz outer tube 11 and a quartz inner tube 7, where two systems composed of gas introducing lines 9 and 5 and gas exhaust lines 12 and 8 are provided inside the quartz tubes 11 and 7, and the gas introducing lines 9 and 5 and the gas exhaust lines 12 and 8 are alternately changed with each other at the vapor growth of a film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low pressure vapor phase growth apparatus, and more particularly to a low pressure vapor phase growth apparatus used for manufacturing semiconductor devices.

[0002]

2. Description of the Related Art As shown in FIG. 3, a conventional vertical reduced pressure vapor deposition apparatus has a quartz outer tube 11 surrounded by a heater 4, and a central portion of the quartz outer tube 11 and inner tube 7 on a front hatch 6. A large number of semiconductor wafers 10 are arranged in the chamber, the exhaust switching valve 16 is opened during depressurization by the rotary pump 15 of the pump exhaust system 14 during vapor phase growth, and then the gas switching valve 3 is opened to allow the reaction gas to flow in only one direction. It had the function of performing flow vapor phase growth.

[0003]

Conventionally, in this type of low pressure vapor phase growth apparatus, when the gas is introduced from the lower part of the quartz tube, the vapor phase growth is carried out in one direction in which the exhaust is drawn from the upper part on the opposite side. In order to obtain a uniform thickness, the reaction chamber in the apparatus was grown with a temperature gradient, but there was a problem that the quality of the grown film varied and the electrical characteristics were affected.

[0004]

The reduced pressure vapor phase growth apparatus of the present invention is a reduced pressure vapor phase growth apparatus provided with an outer tube and an inner tube of quartz, and a gas introduction line and a gas are provided in the quartz tube between the outer and inner tubes. It has two exhaust lines each, and by changing the gas exhaust line and the gas introduction line alternately during vapor phase growth, it is possible to improve the film thickness uniformity without a temperature gradient in the reaction chamber in the apparatus. I have it.

[0005]

The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view showing a vertical vapor phase growth apparatus according to an embodiment of the present invention. It has a quartz outer tube 11 and an inner tube 7 surrounded by a heater 4, and a pump exhaust system 1 between them.
No. 4 rotary pump 15 has a first exhaust switching valve 13
A first exhaust pipe 8 connected via the second exhaust pipe 12 and a second exhaust pipe 12 connected via the second exhaust switching valve 16 are arranged. Further, the first gas pipe 9 for introducing the reaction gas 1 through the first gas switching valve 2 is arranged so as to penetrate through the back hatch 17, and the reaction gas 1 is introduced through the second gas switching valve 3. The second gas pipe 5 is arranged between the front hatch 6 and the outer pipe 11.

When a low pressure vapor phase growth of an insulating film or the like is performed on a large number of semiconductor wafers 10 on the front hatch 6, first of all,
Of the quartz outer tube 11, the back hatch 17 and the front hatch 6 is decompressed by the first exhaust pipe 8 and the second gas switch valve 3 is opened to open the second gas pipe. The reaction gas 1 is introduced from 5 and vapor phase growth is performed for a set time. Next, the first exhaust gas switching valve 13 and the second gas switching valve 3 are closed, the second exhaust gas switching valve 16 is opened, and exhaust is performed through the second exhaust pipe 12, and the first gas switching valve 2 is opened. The reaction gas 1 is introduced from the gas pipe 9 of No. 1 to perform vapor phase growth.

By repeating the above sequence several times, a vapor phase growth film with good uniformity can be formed without a temperature gradient in the reaction chamber in the apparatus.

FIG. 2 shows a horizontal reduced pressure vapor phase growth apparatus as another embodiment of the present invention. In FIG. 2, the same or similar functions as those in FIG. 1 are designated by the same reference numerals.

Even in this horizontal depressurization vapor phase growth, by alternately switching the gas introduction line and the gas exhaust line, a vapor phase growth film having good uniformity can be obtained without a temperature gradient in the reaction chamber in the apparatus. .

[0011]

As described above, according to the present invention, the gas introducing line and the gas exhausting line each have two systems at the time of vapor phase growth, and the lines are alternately switched so that the reaction chambers in the apparatus are as shown in FIG. It has an effect that a vapor-phase growth film having good uniformity can be grown without a temperature gradient.

FIG. 4A shows the relationship between the growth temperature (white circles) and the film thickness (nanometers (nm)) (black circles) in the center, upper part and lower part of the chamber (reaction chamber) by the conventional apparatus of FIG. On the other hand, FIG. 4 (B) shows the relationship between the growth temperature (white circles) and the film thickness (nanometers) (black circles) in the center, upper part and lower part of the chamber (reaction chamber) according to the apparatus of the present invention in FIG. ing.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an embodiment of the present invention.

FIG. 2 is a sectional view showing the outline of another embodiment of the present invention.

FIG. 3 is a sectional view showing the outline of a conventional reduced pressure vapor phase growth apparatus.

FIG. 4 is an explanatory diagram showing temperature distribution and film thickness uniformity between a conventional method and the present invention.

[Explanation of symbols]

 1 Reaction Gas 2 First Gas Switching Valve 3 Second Gas Switching Valve 4 Heater 5 Second Gas Pipe 6 Front Hatch 7 Inner Pipe 8 First Exhaust Pipe 9 First Gas Pipe 10 Semiconductor Wafer 11 Quartz Outer Pipe 12 Second exhaust pipe 13 First exhaust switching valve 14 Pump exhaust system 15 Rotary pump 16 Second exhaust switching valve 17 Back hatch

Claims (1)

[Claims] 1. A quartz tube between an outer tube and an inner tube of quartz has two gas introduction lines and two gas introduction lines, and the gas exhaust line and the gas introduction line are alternately changed during vapor phase growth. A reduced pressure vapor phase growth apparatus characterized by the above.