JPH1015378A - Method for controlling pressure of vacuum treatment chamber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cut useless time during pressure control operation and to try to improve throughput by a method in which at the beginning of controlling the pressure of a vacuum tank, gas is introduced with the tank closed, and when the pressure reaches a prescribed value, a pressure control line is opened to control the pressure by a variable conductance valve. SOLUTION: In controlling pressure of a vacuum treatment chamber in a semiconductor manufacturing apparatus, a main exhaust valve 6 is opened, a pressure control device 14 is made to be in a fully closed mode, a variable conductance valve 11 is fully closed, a vacuum tank 1 is sealed, and a gas introduction valve 10 is opened to introduce gas. In this operation, the device 14 compares the pressure of the tank 1 with a set value by signals from a vacuum meter 13. When the pressure reaches a set value, change-over to a control mode, a pressure control line valve 8 is opened, and the opening of the valve 11 is controlled. After that, film making treatment is done, after the completion of the film making, the valve 10 is opened, the valve 11 is fully opened, and exhausting is done with an exhaust pump 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor manufacturing apparatus and the like.
The present invention relates to a method for adjusting the pressure of a vacuum processing chamber in various devices and equipment for performing processing in a vacuum or reduced-pressure atmosphere.

[0002]

2. Description of the Related Art In an apparatus such as a semiconductor manufacturing apparatus that performs processing in a vacuum or reduced pressure atmosphere, the pressure in the vacuum processing chamber is repeatedly restored and reduced for each processing.

Referring to FIG. 1, a semiconductor manufacturing apparatus as an example of a vacuum processing chamber, in particular, a single-wafer type vacuum processing chamber will be described.

An upper electrode 2 and a lower electrode 3 are provided inside the vacuum chamber 1 so as to face each other up and down. A high frequency power supply 4 is connected to the upper electrode 2, and a high frequency power is applied between the upper electrode 2 and the lower electrode 3. Power is applied. Further, a gas introduction line 5 is connected to the vacuum chamber 1, an exhaust line 7 is connected via a main exhaust valve 6, and a pressure adjustment line 9 is connected via a pressure adjustment line valve 8. The introduction line 5 is provided with a gas introduction valve 10, and the pressure regulation line 9 is provided with a variable conductance valve (VCV: Variab).
The exhaust line 7 joins the pressure regulating line 9 downstream of the variable conductance valve 11, and an exhaust pump 12 is provided downstream of the junction.

[0005] The vacuum chamber 1 is provided with a vacuum gauge 13.
The pressure detected by the vacuum gauge 13 is measured by a pressure controller (APC: A
auto Pressure Controller) 1
The pressure controller 14 controls the opening degree of the variable conductance valve 11 based on the detected pressure to control the inside of the vacuum chamber 1 to a predetermined pressure.

When a wafer is processed in the vacuum processing chamber, a wafer (not shown) is carried into the vacuum chamber 1 by a carrier (not shown) and placed on the lower electrode 3. The inside of the vacuum chamber 1 is evacuated by the exhaust pump 12. When the processing of the wafer is started, the gas introduction valve 10 is opened, a reaction gas is introduced from the gas introduction line 5, and pressure regulation is started. Next, high-frequency power is applied between the upper electrode 2 and the lower electrode 3 to generate plasma to form a thin film on the wafer surface or to etch the thin film on the wafer surface.

When the processing of the wafer is completed, the inside of the vacuum chamber 1 is evacuated again, and when the required degree of vacuum is reached, the wafer is unloaded from the vacuum chamber 1 by a carrier (not shown). The above operation is repeated, and the processing of the wafer is continued.

Referring to FIG. 4, a conventional method for adjusting the pressure of a vacuum processing chamber will be described.

In the initial state of pressure regulation after the processing is completed, the main exhaust valve 6 is opened, the pressure regulation line valve 8 is closed, the pressure controller 14 is in a fully open mode, the variable conductance valve 11 is fully open, The gas introduction valve 10 is closed. When shifting from this state to the pressure adjustment start state, the main exhaust valve 6 closes, the pressure adjustment line valve 8 opens, and the pressure controller 14
Is in the control mode, and the variable conductance valve 11 is in the control mode. When the pressure is further adjusted, the gas introduction valve 1
Open 0 and introduce gas. The pressure controller 14 determines that the pressure inside the vacuum chamber 1 is lower than a set pressure based on a signal from the vacuum gauge 13 and operates the variable conductance valve 11 in a closing direction to adjust the pressure.

A film forming process is performed, and when the film forming is completed, exhaust is performed. For the exhaust, the gas introduction valve 10 is closed, the main exhaust valve 6 is opened, the pressure regulating line valve 8 is closed, and the variable conductance valve 11 is fully opened by the pressure controller 14, and the exhaust is performed by the exhaust pump 12. When the required degree of vacuum is reached, a series of sequences for wafer processing is completed.

FIG. 6 is a diagram showing a change in pressure in the vacuum chamber 1 according to the above-mentioned conventional method of adjusting the pressure of the vacuum processing chamber. Even when the film forming process is started and the reactant gas is introduced from the gas introduction line 5, a closing signal is issued from the pressure controller 14 to the variable conductance valve 11 until the variable conductance valve 11 closes. The introduced reaction gas is exhausted through the pressure regulating line 9, and the pressure does not rise or the rise becomes slow. Therefore, there is wasted time before the pressure actually rises.

[0012]

In the film forming process of the above-mentioned semiconductor manufacturing apparatus, a pressure adjusting time is always required, and the film forming process of the wafer is not performed at the time of the pressure adjusting. Time.

In particular, in the single-wafer-type semiconductor manufacturing apparatus as described above, since the pressure adjustment operation is performed on each processing substrate, the length of the pressure adjustment time directly affects the throughput. As described above, in the conventional method of adjusting the pressure in the vacuum processing chamber, a wasteful time is generated in the pressure adjusting operation, which is an obstacle to improving the throughput.

The present invention has been made in view of the above circumstances, and aims to improve the throughput by eliminating unnecessary time during the pressure adjustment operation.

[0015]

SUMMARY OF THE INVENTION The present invention is directed to a vacuum tank in which a gas introduction line, an exhaust line and a pressure control line communicate with each other, and the pressure control line has a variable conductance valve. In a sealed state, a gas is introduced from the gas introduction line, and when a predetermined pressure is reached, the pressure regulation line is opened to regulate the pressure by the variable conductance valve. A gas introduction line, an exhaust line, and a pressure regulation line communicating with each other, the gas introduction line having a gas introduction valve, the exhaust line having a main exhaust valve, the pressure regulation line being a pressure regulation line valve and a variable conductance, In a vacuum chamber having a valve, when pressure adjustment is started from a reduced pressure state of the vacuum chamber, the main exhaust valve is closed, and the pressure adjustment line valve and the variable conductance are closed. The present invention relates to a pressure control method for a vacuum processing chamber, in which at least one of the above is forcibly fully closed, the gas introduction valve is opened to introduce gas, and when a predetermined pressure is reached, the pressure is regulated by the variable conductance valve. .

Therefore, in the present invention, the introduced gas is stored in the vacuum tank for pressurization without wasting since the vacuum tank is in a sealed state in the initial state of pressure adjustment, so that no time is wasted.

[0017]

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

The configuration of the apparatus according to the present embodiment is the same as that of the conventional case where the pressure of the vacuum processing chamber is adjusted, and thus the description thereof is omitted. Referring to FIG. 2, a sequence of pressure regulation in the vacuum processing chamber according to the present embodiment will be described.

In an initial state in which the pressure adjustment is started, the main exhaust valve 6 is opened, the pressure adjustment line valve 8 is closed, the pressure controller 14 is fully opened, the variable conductance valve 11 is fully opened, and the gas introduction valve is opened. 10 is closed. From this state, the state shifts to the pressure adjustment start state, and at the same time, the main exhaust valve 6 is closed, and simultaneously, the pressure controller 14 is set to the fully closed mode, and the variable conductance valve 11 is fully closed. Thus, the vacuum chamber 1 is in a sealed state.

When the pressure is further adjusted, the gas introduction valve 10 is opened to introduce gas. The pressure controller 1
4 compares the pressure of the vacuum chamber 1 with a set pressure according to a signal from the vacuum gauge 13 and switches the pressure controller 14 to a control mode when the set pressure is reached, -1 and sets the pressure regulating line valve 8 to -1. Open, and the opening degree of the variable conductance valve 11 is controlled by the pressure controller 14-2.

A film forming process is performed, and when the film forming is completed, exhaust is performed. For the exhaust, the gas introduction valve 10 is closed, the main exhaust valve 6 is opened, the pressure regulating line valve 8 is closed, and the variable conductance valve 11 is fully opened by the pressure controller 14, and the exhaust is performed by the exhaust pump 12. When the required degree of vacuum is reached, a series of sequences for wafer processing is completed.

FIG. 5 is a diagram showing a change in the pressure in the vacuum chamber 1 according to the method of adjusting the pressure of the vacuum processing chamber according to the present invention. Since the main exhaust valve 6 and the pressure regulating line valve 8 are fully closed and the vacuum chamber 1 is sealed, the reaction gas introduced from the gas introduction line 5 is not exhausted unnecessarily, and is delayed from the initial pressure rise. In addition, no dulling occurs, no wasted time is generated, and pressure adjustment can be performed in a short time.

FIG. 3 shows a sequence of pressure regulation in a vacuum processing chamber according to another embodiment.

In the initial state in which the pressure adjustment is started, the main exhaust valve 6 is opened, the pressure adjustment line valve 8 is opened, the pressure controller 14 is fully opened, the variable conductance valve 11 is fully opened, and the gas introduction valve is opened. 10 is closed. From this state, the state shifts to the pressure adjustment start state, and at the same time, the main exhaust valve 6 is closed, and simultaneously, the pressure controller 14 is set to the fully closed mode, and the variable conductance valve 11 is fully closed. Thus, the vacuum chamber 1 is in a state close to containment.

In the pressure regulation state, the gas introduction valve 10 is opened to introduce gas. The pressure controller 14 controls the vacuum gauge 13
The pressure in the vacuum chamber 1 is compared with a set pressure by a signal from the controller, and when the pressure reaches the set pressure, the pressure controller 14 is switched to a control mode-1, and the variable conductance valve 11
Controlling the opening degree of -2.

A film forming process is performed, and when the film forming is completed, exhaust is performed. For the exhaust, the gas introduction valve 10 is closed, the main exhaust valve 6 is opened, the variable conductance valve 11 is fully opened by the pressure controller 14, and the exhaust pump 12 is opened.
To exhaust air. When the required degree of vacuum is reached, a series of sequences for wafer processing is completed.

Also in this embodiment, the main exhaust valve 6 and the variable conductance valve 1
1 is completely closed, and the vacuum chamber 1 is sealed, so that the reaction gas introduced from the gas introduction line 5 is not exhausted unnecessarily. This can prevent the occurrence of an unnecessary time, and can perform pressure adjustment in a short time.

[0028]

As described above, according to the present invention, it is possible to suppress useless time during the pressure adjustment operation and shorten the pressure adjustment time, thereby improving the throughput.

[Brief description of the drawings]

FIG. 1 is a schematic view of a single-wafer semiconductor manufacturing apparatus which is one of the objects of the present invention.

FIG. 2 is a flowchart showing one sequence according to the embodiment of the present invention.

FIG. 3 is a flowchart showing a sequence according to another embodiment of the present invention.

FIG. 4 is a flowchart showing a sequence of a conventional example.

FIG. 5 is a diagram showing a pressure rise curve during pressure regulation according to the embodiment of the present invention.

FIG. 6 is a diagram showing a pressure rise curve during pressure regulation in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum tank 2 Upper electrode 3 Lower electrode 4 High frequency power supply 5 Gas introduction line 6 Main exhaust valve 7 Exhaust line 8 Pressure regulation line valve 9 Pressure regulation line 10 Gas introduction valve 11 Variable conductance valve 12 Exhaust pump 13 Vacuum gauge 14 Pressure controller

Claims (2)

[Claims] In a vacuum chamber having a gas introduction line, an exhaust line, and a pressure control line communicating with each other and the pressure control line having a variable conductance valve, when the pressure control is started, the vacuum chamber is placed in a sealed state, A pressure adjustment method for a vacuum processing chamber, wherein a pressure is introduced by introducing a gas from an introduction line, and when a predetermined pressure is reached, the pressure adjustment line is opened to perform pressure adjustment by the variable conductance valve. 2. A gas introducing line, an exhaust line, and a pressure regulating line are communicated with each other, wherein the gas introducing line has a gas introducing valve, the exhaust line has a main exhaust valve, and the pressure regulating line has a pressure regulating line. In a vacuum vessel having a line valve and a variable conductance valve, when starting pressure regulation from a reduced pressure state of the vacuum vessel, the main exhaust valve is closed and at least one of the pressure regulation line valve and the variable conductance valve is closed. A method for regulating the pressure of a vacuum processing chamber, wherein the pressure is fully closed, the gas is introduced by opening the gas introduction valve, and the pressure is regulated by the variable conductance valve when a predetermined pressure is reached.