JPH04313218A - Semiconductor manufacturing apparatus - Google Patents

Abstract

PURPOSE:To control the state of a pressure inside a reaction chamber by a method wherein information form a pressure gauge is used and a vacuum suction rate and an atmospheric-pressure return rate are input to a controller for operation use. CONSTITUTION:A controller 8A, for operation use, which can set a pressure change rate is provided. The introduction amount of a gas into a reaction chamber 9 and a mechanism for pressure control use are controlled by using the controller 8A for operation use. A pressure is controlled so as to correspond to the pressure change rate.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to semiconductor manufacturing equipment.

0002

2. Description of the Related Art FIG. 3 is a diagram showing the configuration of a conventional horizontal semiconductor manufacturing apparatus using chemical vapor deposition under reduced pressure (hereinafter abbreviated as LP-CVD method), and FIG. 4 is a diagram showing the semiconductor manufacturing apparatus shown in FIG. FIG. 5 is a diagram illustrating a method for controlling the pressure inside the reaction chamber used in the present invention, and FIG. 5 is a diagram showing the relationship between the suction pressure of the exhaust pump and the exhaust speed. In FIG. 3, 1 is a gas inlet, 2 is a gas exhaust pipe, 3 is an exhaust vacuum pump, 4 is a pressure control valve, 5 is a pressure gauge, 6 is a wafer to be processed, 7 is a heater, 8 is an operation controller, 9 is a reaction chamber, and 10 is a flow rate controller.

Next, the operation will be explained. In the semiconductor manufacturing apparatus shown in FIG. 3, when a gas is introduced into the reaction chamber 9 containing the wafer 6 to be processed through the gas introduction port 1 and processing is performed, the following procedure is usually performed. That is, a wafer 6 to be processed on which a film is to be formed is placed in a reaction chamber 9 heated by a heater 7.
After that, the device is operated to maintain airtightness of each part of the device. At this time, no gas is introduced from the gas inlet 1. Thereafter, the interior of the reaction chamber 9 is evacuated using the exhaust vacuum pump 3. In this case, evacuation is performed from normal pressure to a vacuum of about 10 −3 Torr, but this depends on the capacity of the exhaust vacuum pump 3 . As shown in FIG. 5, the relationship between the suction pressure of the evacuation vacuum pump 3 and the evacuation speed shows that the evacuation speed reaches a peak before reaching the desired pressure. That is, evacuation from normal pressure to a desired pressure is not constant, but a large evacuation is performed in the middle, and after reaching an evacuation peak, the amount of evacuation gradually decreases to reach the desired pressure. Thereafter, a film-forming gas is introduced into the reaction chamber 9 through the gas inlet 1, and a film-forming process is performed. After the film formation process is completed, the gas introduction from the gas inlet 1 is stopped, and the inside of the reaction chamber 9 is degassed by the exhaust vacuum pump 3. After that, the exhaust vacuum pump 3 is stopped and the gas is introduced from the gas inlet 1. Inert gas is introduced, the inside of the reaction chamber 9 is returned to atmospheric pressure, and the wafer 6 to be processed is pulled out, and the processing is completed. At this time, the return to normal pressure is usually performed only by controlling the flow rate of inert gas.

0004

[Problems to be Solved by the Invention] Conventional evacuation and return to normal pressure were performed as described above, so
When evacuation is performed inside the reaction chamber 9, the evacuation speed changes when evacuation is performed from normal pressure to a desired pressure because it depends on the capacity of the evacuation vacuum pump 3, so foreign matter within the reaction chamber 9 is rolled up. This foreign material causes defects in VLSIs, which are becoming increasingly highly integrated. Also, when returning to normal pressure, inert gas is introduced through the gas inlet 1 only by controlling the flow rate, so foreign matter in the reaction chamber 9 is rolled up in the same way as vacuuming. Furthermore, when vacuuming and returning to normal pressure,
Although it is a clear fact that rapid pressure changes lead to the generation of foreign matter, there was no good solution to this problem, and the solution was based on experience.

[0005] Therefore, the present invention was made to solve the above-mentioned conventional problems, and its purpose is to:
An object of the present invention is to provide a semiconductor manufacturing apparatus in which the pressure situation in a reaction chamber is controlled by inputting a vacuum evacuation rate and a normal pressure return rate to an operation controller using information from a pressure gauge.

[0006]

[Means for Solving the Problems] In order to achieve the above object, a semiconductor manufacturing apparatus according to the present invention is provided with an operation controller capable of setting a pressure change rate, and a controller for controlling the amount of gas introduced into a reaction chamber and the pressure. The mechanism is controlled by this operation controller, and pressure control is performed according to the rate of pressure change.

[0007]

[Operation] The pressure change rate control mechanism in this invention can set the pressure change rate within the reaction chamber.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be explained in detail with reference to the drawings. 1 and 2 are diagrams for explaining one embodiment of a semiconductor manufacturing apparatus according to the present invention, and FIG. 1 shows a schematic block diagram in which the semiconductor manufacturing apparatus according to the present invention is applied to a horizontal LP-CVD apparatus system, and FIG. 2 is a diagram illustrating the setting of the pressure change rate and its operation in the semiconductor manufacturing apparatus applied to FIG. 1. FIG. Next, the operation will be explained. In the horizontal LP-CVD apparatus shown in FIG. 1, when a gas is introduced from the gas inlet 1 into the reaction chamber 9 containing the wafer 6 to be processed for processing, the following procedure is usually performed. That is, a wafer 6 to be processed on which a film is to be formed is introduced into a reaction chamber 9 heated by a heater 7, and then operations are performed to maintain airtightness of each part of the apparatus. Thereafter, the interior of the reaction chamber 9 is evacuated using the exhaust vacuum pump 3. In this case, from normal pressure to 10-
Vacuuming is performed to a degree of vacuum of approximately 3 Torr, but since the rate of pressure change is set by the operation controller 8A, the pressure control valve 4 must be adjusted to obtain the exhaust from the exhaust vacuum pump 3 and the set rate of pressure change. An inert gas is introduced into the reaction chamber 9 from the gas inlet 1 through the flow rate controller 10. Through these operations, the rate of pressure change in the reaction chamber 9 is kept constant to obtain a desired pressure. Thereafter, a film-forming gas is introduced into the reaction chamber 9 through the gas inlet 1, and a film-forming process is performed. After the film formation process is completed, stop introducing gas from gas inlet 1,
After the reaction chamber 9 is degassed by the exhaust vacuum pump 3, the pressure change rate is set, so the pressure control valve 4 is adjusted and the inert gas is injected from the gas inlet 1 in the same way as when evacuation. is introduced into the reaction chamber 9 through the flow rate controller 10,
The rate of pressure change remains constant and the pressure returns to atmospheric pressure. This completes the return to normal pressure, pulls out the wafer 6 to be processed, and ends the process.

[0009] In the above-mentioned embodiment, the horizontal LP-C
Although the case in which a VD device is used has been described, any device that alternately repeats vacuum and atmospheric pressure may be used, and the same effects as in the above-described embodiments can be obtained.

Further, in the above-mentioned embodiments, a case has been described in which the pressure gauge is provided at the end of the reaction chamber on the gas inlet side as shown in FIG. 1, but the present invention is not limited thereto.

Further, in the above-mentioned embodiment, a case was explained in which a pressure control method based on the degree of opening and closing of a pressure control valve was used as a pressure control mechanism, but the present invention is not limited to this. The same effect as described above can be obtained using a ballast method in which inert gas is sent into the pump, or a pressure control mechanism that controls the evacuation capacity of the vacuum pump itself.

0012

Effects of the Invention As described above, the semiconductor manufacturing apparatus according to the present invention is equipped with an operation controller that can set the rate of pressure change, and has a mechanism for controlling the amount of gas introduced into the reaction chamber and the pressure for this operation. Since it is controlled by a controller and the pressure is controlled according to the rate of pressure change, there is no need to take preventive measures based on experience against foreign matter being stirred up in the reaction chamber, and it has the extremely excellent effect of being able to perform quantitative monitoring. can get.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing a configuration when a semiconductor manufacturing apparatus according to an embodiment of the present invention is applied to a horizontal LP-CVD apparatus system.

FIG. 2 is a schematic diagram illustrating setting of a pressure change rate and its operation in the semiconductor manufacturing apparatus applied to FIG. 1;

FIG. 3 is a schematic block diagram showing the configuration of a conventional horizontal LP-CVD apparatus system.

4 is a schematic diagram illustrating a pressure control method used in the semiconductor control device shown in FIG. 3. FIG.

FIG. 5 is a diagram showing the relationship between the suction pressure and exhaust speed of the exhaust pump.

[Explanation of symbols]

1 Gas inlet 2 Gas exhaust pipe 3 Exhaust vacuum pump 4 Pressure control valve 5 Pressure gauge 6 Wafer to be processed 7 Heater 8A Operation controller 9
Reaction chamber 10 flow rate controller

Claims (1)

[Claims] 1. An operation controller capable of setting a pressure change rate, the operation controller controlling the amount of gas introduced into the vacuum chamber and a pressure control mechanism, and controlling the pressure according to a desired pressure change rate. A semiconductor manufacturing device characterized by performing the following steps.