JPH01237366A - Vacuum device - Google Patents

Abstract

PURPOSE:To shorten the opening/closing time of a pressure control valve and improve the capacity of a vacuum device by connecting a by-pass valve in parallel to a pressure control valve wherein a vacuum pump is connected to a vacuum system through the pressure control valve. CONSTITUTION:A reaction gas G is introduced into a vacuum system 1 of a vacuum device through MFG 6 and a reaction gas control valve 7 from a reaction gas inlet 3A of an upper electrode 3 connected to a high frequency electric source 5. A vacuum pump 11 is connected to an outlet 2A of an lower electrode 2 in the vacuum system 1 through a main valve 8 and an automatic pressure control valve 9 which are connected to each other in series. In this constitution, the connecting route of the vacuum system 1 to the vacuum pump 11 is provided with a by-pass line 10A for connecting the both ends of the automatic pressure control valve 9. In the by-pass line 10A, a butterfly or needle by-pass valve 10 is disposed in parallel to the automatic pressure control valve 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum device, and in particular to a technique that is effective when applied to vacuum devices such as dry etching devices and plasma CVD devices used in semiconductor manufacturing technology. It is something.

[Conventional technology]

In semiconductor manufacturing technology, a plasma CVD apparatus for forming a thin film on the surface of a semiconductor wafer and a dry etching apparatus for etching the thin film are used. This type of manufacturing equipment is a reaction chamber (vacuum system) that processes semiconductor wafers.
A vacuum pump is connected to the vacuum pump through a main valve and an automatic pressure control valve connected in series.

Each of the main valve and automatic pressure control valve is configured with either a butterfly valve type or a needle valve type. The vacuum pump is configured to evacuate the reaction chamber.

The automatic pressure control valve is configured to control the conductance between the reaction chamber and the vacuum pump so that the pressure inside the reaction chamber can be controlled at a constant level.

In the above-mentioned manufacturing apparatus, first, a semiconductor tool is housed in a reaction chamber, and then a predetermined reaction gas is introduced into the reaction chamber. Next, the reaction gas in the reaction chamber is pulled by a vacuum pump, and the automatic pressure control valve is fully opened (for example, the degree of opening/closing is 100%).
) to almost closed state (e.g. degree of opening/closing 20 to 30)
[%co)] and adjust the pressure of the reaction gas in the reaction chamber. Next, the semiconductor wafer is processed in the reaction chamber, and after the processing, the automatic pressure control valve is fully opened and the reaction gas remaining in the reaction chamber is exhausted by a vacuum pump. Next, the processed semiconductor wafer is taken out from the reaction chamber. Then, a new unprocessed semiconductor wafer of the next stage is placed in this reaction chamber, and the above-described steps are repeated.

[Problem to be solved by the invention]

However, the above-described manufacturing apparatus requires time to operate the automatic pressure control valve from a nearly closed state to a fully open state after processing of a semiconductor wafer is completed. Therefore, the reaction gas remaining in the reaction chamber cannot be efficiently exhausted, and it takes time to exhaust the reaction gas. In addition, after the first stage treatment is completed, the reaction gas is introduced into the reaction chamber for the next stage treatment, and the automatic pressure control valve is kept from fully open to almost closed in order to adjust the pressure of the reaction gas in the reaction chamber. It requires time to operate. Therefore, it takes time to adjust the pressure of the reaction gas in the reaction chamber. Therefore, the throughput of the manufacturing equipment is substantially reduced, resulting in a problem that it takes longer to complete the semiconductor product.

On the other hand, in order to improve the throughput of manufacturing equipment, it is conceivable to speed up the opening and closing operations of automatic pressure control valves. However, the faster the automatic pressure control valve opens and closes, the more a hunting phenomenon occurs in which the pressure continuously fluctuates in the vicinity of the set pressure of the reaction gas in the reaction chamber.

For this reason, it has not been possible to improve the throughput of the manufacturing apparatus by speeding up the opening and closing operations of the automatic pressure control valve.

The object of the present invention is to provide a dry etching apparatus, a plasma CV
The purpose of the present invention is to provide a technology that can improve processing capacity and shorten processing time in vacuum equipment such as D equipment.

An object of the present invention is to provide a technique capable of shortening the opening/closing operation time of a pressure control valve and achieving the above object.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means for Solving the Problems] Among the inventions disclosed in this application, a brief overview of typical inventions is as follows.

In a vacuum device in which a vacuum pump is connected to a vacuum system through a pressure control valve, a bypass valve is provided that is connected in parallel to the pressure control valve.

[For production]

According to the above-described means, gas in the vacuum system can be exhausted through the bypass valve while the pressure control valve is maintained at an opening/closing degree that sets the gas pressure in the vacuum system to a predetermined pressure. The opening/closing operation time of the pressure control valve from adjusting the gas pressure in the vacuum system to exhausting the gas in the vacuum system can be shortened. Further, while the pressure control valve is held at an opening/closing degree that sets the gas pressure in the vacuum system to a predetermined pressure, the bypass valve is closed to introduce gas into the vacuum system, and the opening/closing degree of the pressure control valve is slightly changed. Since the pressure of the gas in the vacuum system is adjusted by making fine adjustments to can.

As a result, the processing capacity of the vacuum device can be improved and the processing time can be shortened.

Hereinafter, the structure of the present invention will be explained together with an embodiment in which the present invention is applied to a dry etching apparatus.

In addition, in all the figures for explaining the embodiment, parts having the same functions are given the same reference numerals, and repeated explanations thereof will be omitted.

〔Example〕

FIG. 1 (block diagram) shows a schematic configuration of a dry etching apparatus (vacuum apparatus) which is an embodiment of the present invention.

As shown in Figure 1, the reaction chamber (
The vacuum system) 1 is provided with a lower electrode 2 on the lower side of the interior and an upper electrode 3 on the upper side of the interior. The structure is such that a semiconductor wafer 4 as a material to be etched can be placed on the surface of the lower electrode 2. This lower electrode 2 is connected to ground potential. The upper electrode 3 is connected to a high frequency power source 5.

A reaction gas G is introduced into the reaction chamber 1 . The reaction gas G is first supplied to a mass flow controller (MFC) 6 through a reaction gas introduction pipe, and its flow rate is controlled.

Next, the reactant gas G whose flow rate is controlled is introduced into the reaction chamber 1 through the reactant gas inlet 3A provided in the upper electrode 3 via the reactant gas control valve 7. The reaction gas control valve 7 is constructed of a butterfly valve type, a needle valve type, or the like.

An exhaust port 2A is provided around the lower electrode 2 of the reaction chamber 1. A vacuum pump 11 is connected to the exhaust port 2A through a main valve 8 and an automatic pressure control valve 9, which are connected in series. Each of the main valve 8 and the automatic pressure control valve 9 is configured by a butterfly type, a needle valve type, etc., similarly to the above-mentioned reaction gas control valve 7. The main valve 8 and the automatic pressure control valve 9 are each configured to drive each movable valve (valve) by a drive mechanism such as a motor mechanism, a pneumatic mechanism, or a hydraulic mechanism. The operation of the drive mechanism is mainly controlled by a microcomputer.

In the connection path between the reaction chamber 1 and the vacuum pump 11, there is a bypass line (
An exhaust route detour pipe) 10A and a bypass valve 10 arranged on the route are provided.

That is, the bypass valve 10 is an automatic pressure control valve 9.
are connected in parallel. The bypass valve 10 is constructed in the same manner as the main valve 8 and the automatic pressure control valve 9 described above.

Next, the processing operation of the dry etching apparatus described above will be briefly explained using FIG. 1 and Table 1 (page 15 of the same specification).

First, a semiconductor wafer (material to be etched) 4 is placed on the surface of the lower electrode 2 in the reaction chamber 1 . This mounting of the semiconductor wafers 4 is performed by a batch processing method or a single wafer processing method.

Next, as shown in Step 1 of FIG. 1 and Table 1, the reaction gas control valve 7 is fully opened (opening/closing degree 100 [%]), and the reaction gas G whose flow rate is controlled through the mass flow controller 6 is supplied to the reaction chamber. Introduce it inside 1.

After introducing this reaction gas G, the main valve 8 is fully opened (
The opening/closing degree is set to 100%), and the inside of the reaction chamber 1 is evacuated by the vacuum pump 11 through the automatic pressure control valve 9. At this time, the automatic pressure control valve 9 is kept mostly closed (opening/closing degree 20 to 30%), and the reaction chamber 1
The pressure of the reaction gas G inside is adjusted to a predetermined set value.

When adjusting the pressure of the reaction gas G, the bypass valve 10 is in a fully closed state (opening/closing degree 0%). Then, when the pressure of the reaction gas G inside the reaction chamber 1 is adjusted, the surface of the semiconductor wafer 4 is subjected to a dry etching process.

Next, after the dry etching process is completed, as shown in step 2 of FIG. 1 and Table 1, the reaction gas control valve 7 is opened.
is fully open (opening/closing degree O [%]) and the bypass valve 10 is fully open (opening/closing degree 100 [%]), the inside of the reaction chamber 1 is evacuated by the vacuum pump 11, and the inside of the reaction chamber 1 is evacuated. The remaining reaction gas (exhaust gas) G is exhausted. At this time, the main valve 8 is fully opened (
The automatic pressure control valve 9 is maintained at an almost closed state (opening/closing degree of 20 to 30%) as in the previous processing step. In other words, the automatic pressure control valve 9 is in a state where it hardly operates.

This holding is performed under the control of a microcomputer that controls the main valve 8 and the automatic pressure control valve 9.

The reaction gas G remaining inside the reaction chamber 1 can be efficiently and immediately exhausted through the bypass valve 10 in a fully open state.

Next, the semiconductor wafer 4 that has been subjected to the dry etching process is transported from inside the reaction chamber 1 to the next processing step. Then, a semiconductor wafer 4 that has undergone the previous processing step is newly placed on the surface of the lower electrode 2 inside the reaction chamber 1 of the dry etching apparatus. Then, as shown in Step 3 of FIG. 1 and Table 1, the same steps as Step 1 are repeated.

At this time, the automatic pressure control valve 8 is in an almost closed state (opening/closing degree of 20 to 30 [%]), which was maintained during the exhaustion of the reaction gas G in the previous step, so the opening/closing degree is only slightly adjusted. The pressure of the reaction gas G inside the reaction chamber 1 can be adjusted to the above-mentioned set value.

As described above, in a dry etching apparatus in which a vacuum pump 11 is connected to the reaction chamber (vacuum system) 1 through an automatic pressure control valve 9, a bypass valve 10 connected in parallel to the automatic pressure control valve 9 is provided. The automatic pressure control valve 9 is controlled to control the reaction gas G inside the reaction chamber 1.
The opening/closing degree that sets the pressure at a predetermined pressure (for example, opening/closing degree 2)
Since the reaction gas G inside the reaction chamber 1 can be exhausted through the bypass valve 10 in a state where the reaction gas G inside the reaction chamber 1 is maintained at 0 to 30%, the pressure of the reaction gas G inside the reaction chamber 1 can be adjusted. The opening/closing operation time of the automatic pressure control valve 9 until the reaction gas G inside the reactor 1 is exhausted can be shortened.

Further, while the automatic pressure control valve 9 is maintained at an opening/closing degree that sets the pressure of the reaction gas G inside the reaction chamber 1 to a predetermined pressure (for example, an opening/closing degree of 20 to 30%), the bypass valve 10 is Close the reactor gas G inside the reaction chamber 1.
The pressure of the reaction gas G inside the reaction chamber 1 is adjusted by slightly adjusting the degree of opening and closing of the automatic pressure control valve 9. The time required for the automatic pressure control valve 9 to open and close until the pressure of the reaction gas G inside the chamber 1 is adjusted can be shortened. When adjusting the pressure of the reaction gas G, the degree of opening and closing of the automatic pressure control valve 9 hardly changes, so no hunting phenomenon occurs.

As a result, in the dry etching apparatus, the number of semiconductor wafers 4 that can be dry etched per unit time can be increased and the processing capacity can be improved, so the processing time required to complete the semiconductor product can be shortened. .

FIGS. 2 and 3 (block configuration diagrams) show a schematic configuration of a dry etching apparatus (vacuum apparatus) according to another embodiment of the present invention.

The dry etching device shown in FIG. 2 has a main valve 8.
An automatic pressure control valve 9 is provided on the reaction chamber 1 side, and a bypass valve 10 is connected in parallel to this automatic pressure control valve 9.

In the dry etching apparatus shown in FIG. 3, an automatic pressure control valve 9 and a main valve 8 are connected in series from the reaction chamber 1 side, and a bypass valve 10 is connected in parallel to the automatic pressure control valve 9 and the main valve 8. Connected.

The dry etching device shown in FIG. 4 has a main valve 8.
, automatic pressure control valves 9 are sequentially connected in series from the reaction chamber 1 side, and a bypass valve 10 is connected in parallel to the main valve 8 and automatic pressure control valve 9.

In either case, the same effects as the dry etching apparatus of the above-mentioned embodiment can be achieved.

As above, the invention made by the present inventor has been specifically explained based on the above embodiments, but the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist thereof. Of course.

For example, the present invention can be widely applied to a vacuum device such as a plasma CVD device in which a vacuum pump is connected to the vacuum system through a pressure control valve.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

The opening and closing operation time of the pressure control valve of the vacuum device can be shortened, and the processing time of the vacuum device can be shortened.

Below is the margin (Table 1 1 Below is the margin

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of a dry etching device (vacuum device) which is one embodiment of the present invention, and FIGS. 2 to 4 are dry etching devices which are other embodiments of the present invention. 1 is a block configuration diagram showing a schematic configuration of a (vacuum device). In the figure, 1... reaction chamber (vacuum chamber), 8... main valve,
9...Automatic pressure control valve, 10...Bypass valve, 10A...Bypass line.

Claims (1)

[Claims] 1. A vacuum device in which a vacuum pump is connected to a vacuum system via a pressure control valve, characterized in that a bypass valve is provided in parallel to the pressure control valve. 2. The vacuum device according to claim 1, wherein the bypass valve is constructed of a butterfly valve type or a needle valve type.