JPS6213030A - Vacuum device - Google Patents

Abstract

PURPOSE:To largely improve the safety of a vacuum device by disposing a cover having airtightness and flexibility on the outer periphery of a portion made of a flexible tube of a connecting member, and providing means for detecting the state change of a sealed space. CONSTITUTION:Reacted gas produced in a vacuum vessel 11 is transported through the interior of a connecting part 19a and through a vacuum pump 16, further treated by exhaust gas treating means 18, and exhausted into the atmosphere. Since an airtight cover 19b is disposed on the outer periphery of a connecting member 19a, even if the member 19a is corroded by the transporting gas so that a hole is opened, the gas is not leaked to the atmosphere. Nitrogen gas is sealed at 1.5atm in a space between the member 19a and the cover 19b to detect the pressure change by a pressure sensor 20, and fed back to control system of a vacuum device body. Thus, the safety of the vacuum device can be improved.

Description

Detailed Description of the Invention: Industrial Field of Application (2 pages) The present invention relates to a dry etching apparatus for etching a workpiece using low-temperature plasma, and a plasma CVD (Chemical VaporDep)
The present invention relates to a vacuum device used in a plasma CVD device or the like for depositing a thin film on the surface of a workpiece by an os i t i on method.

Conventional technology In recent years, equipment that uses low-temperature plasma is semiconductors.

It has become indispensable in the manufacturing process of electronic components. In particular, the introduction of dry etching methods and plasma CVD methods into manufacturing processes has rapidly become more prominent.

In the dry etching method, a base material is held in a vacuum container, a compound gas containing a halogen element is supplied, the pressure is kept constant at a predetermined level, and then the compound gas is excited with high frequency energy or DC power. This is a method in which etching is performed by generating low-temperature plasma and bringing the substrate into contact with active radical particles or ions in the low-temperature plasma.

3-. In the plasma CVD method, after holding a base material in a vacuum container and supplying a compound gas containing the constituent elements of the thin film to be formed,
Exciting the compound gas by high frequency energy or the like,
That is, this is a method of depositing a thin film on the surface of a substrate by turning it into a low-temperature plasma and placing the substrate in an atmosphere of low-temperature plasma.

By the way, those dry etching devices, plasma C
Efforts have been made to reduce the area occupied by the clean room and to reduce dust in the clean room by installing an evacuation means such as a vacuum pump outside the clean room in the VD device. Flexible tubes are often used to airtightly connect the device body in the clean room and the gas exhaust device located outside the clean room, from the viewpoint of saving piping construction costs and ease of maintenance.

An example of a vacuum apparatus used in the conventional low-temperature plasma reactor described above will be described below with reference to the drawings.

FIG. 2 shows a schematic cross-sectional view of a vacuum device used in a dry etching device, which is a conventional low-temperature plasma reactor.

In Figure 2, 1 is a vacuum container that can maintain a vacuum state, 2 is an electrode that can generate gas plasma in the vacuum container 1 and is supplied with high-frequency power, and 3 is held on electrode 2. 4 is a grounded electrode, 5 is a gas supply nozzle for introducing gas into the vacuum container 1, and 6 is a vacuum pump for evacuating the inside of the vacuum container 1. 7 is a pressure control device for making the conductance in the piping variable and controlling the pressure in the vacuum container 1; 8 is an exhaust gas treatment device; 9 is a vacuum container 1, a vacuum pump 6, and a vacuum pump 6; It is a flexible tube with a thin wall structure in order to connect the exhaust gas treatment means 8 and the exhaust gas treatment means 8 airtightly and to easily change the direction.

The operation of the dry etching apparatus configured as described above for dry etching the aluminum film on the base material 3 will be described below.

First, the inside of the vacuum container 1 is evacuated to 5 pages and 1 mTorr or less by the vacuum pump 6, and then, inside the vacuum container 1,
A gas containing chlorine groups, that is, a mixed gas of chlorine and boron chloride, is introduced through the nozzle 6, and the pressure inside the vacuum container 1 is maintained at a constant pressure of about 10 mTorr by the pressure control device 7. Next, the frequency of 13.56MH was applied to electrode 2.
By supplying high-frequency power 2, low-temperature plasma is generated in the space containing the base material 3, that is, the space between the electrode 2 and the earth electrode 4, and the mixed gas of chlorine and boron chloride is electrically excited and activated. state. The base material 3 has aluminum exposed in a pattern through a resist mask, and the aluminum comes into contact with the activated gas. As a result, the aluminum is etched according to the pattern, making it possible to form an aluminum wiring circuit. Here, during etching, the excited gas that has been used effectively, the excited mixed gas, and the reaction product gas generated as a result of dry etching are passed through the flexible tube 9 to the vacuum pump 6 and the exhaust gas treatment means. It passes through route 8 and is released into the atmosphere.

Page 6 Incidentally, the flexible tube 9 is generally manufactured with a wall thickness of 1 mm or less in order to provide flexibility. Further, in order to cope with the active gas, corrosion-resistant stainless steel such as 5US316 is often used as the material.

Problems to be Solved by the Invention However, as shown in the table above, in the configuration shown above, even if a corrosion-resistant material is used for the flexible tube 9, the chlorine-based excited gas is highly active and a chemical reaction occurs. Cheap. Particularly, areas where stress is concentrated, such as curved parts, are more likely to react, and if the wall thickness is thin, as corrosion progresses,
This has the problem of increasing the risk of chlorine-based gas leaking outside the gas transport route, which is harmful to the human body.

In view of the above-mentioned problems, the present invention provides a vacuum device that prevents transport gas from leaking outside the gas transport path and greatly improves the safety of the device.

Means for Solving the Problems In order to solve the above-mentioned problems, the vacuum device 7 of the present invention has a gas transport connection for airtightly connecting the vacuum container and the vacuum pump, and the vacuum pump and the exhaust gas treatment means. At least a part of the member is made of a flexible tube, and an airtight and flexible cover is disposed on the outer periphery of the part of the connecting member that is made up of at least seven flexiple tubes, and a cover that is airtight and flexible is arranged between the connecting member and the cover. The system is equipped with means for detecting changes in the state of the sealed space between the two.

Effect of the Invention According to the above-described structure, even if the pipe wall of the connecting member is corroded and a hole is formed, an airtight cover is provided on the outer periphery of the connecting member, so that the gas transport path can be maintained. The risk of transport gas leaking to other areas can be greatly reduced. Furthermore, by detecting changes in the state of the space between the connecting member and the cover, such as changes in pressure, it is possible to detect whether or not the conduit wall of the connecting member has corroded and a hole has formed, and the detection signal This makes it possible to automatically perform safe operation of the low-temperature plasma reactor, thereby making it possible to greatly improve the safety of the device.

EXAMPLE Hereinafter, a vacuum apparatus according to an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic front sectional view of a vacuum apparatus in a first embodiment of the present invention.

In FIG. 1, 11 is a vacuum container that can maintain a vacuum state, 12 is an electrode that can generate low-temperature plasma in the vacuum container 11 and is supplied with high-frequency power at a frequency of 13.56 MHz, and 13 is an electrode that can generate low-temperature plasma in the vacuum container 11. A base material which is held by an electrode 12 and is a workpiece to be dry etched; 14 is a grounded electrode; 16 is a gas supply nozzle for introducing gas into the vacuum container 11; A vacuum pump for evacuating the inside of the vacuum container 11, 17 a pressure control device for varying the conductance in the piping and controlling the pressure inside the vacuum container 11, and 18 a vacuum pump 1.
6 is an exhaust gas treatment means for making the exhaust gas harmless to the human body and releasing it into the atmosphere after treating the exhaust gas by employing an adsorption method, for example; 19 is the outer periphery of a flexible tube nope for gas transportation; 19a is a connecting member at least partially composed of 7 lexiple tubes; 19b is a cover; 20 is a connecting member 19a and cover 1;
This is a pressure sensor that serves as a means for detecting a change in the state of the space, that is, a change in pressure, between the holder and the holder 9b.

The operation of the vacuum apparatus configured as described above will be explained below.

First, the inside of the vacuum container 11 is heated to 1 mTo by the vacuum pump 16.
After evacuation to below rr, a gas containing a chlorine group, that is, a mixed gas of chlorine and boron chloride, is introduced into the vacuum container 11 through the nozzle 15, and the pressure inside the vacuum container 11 is controlled by the pressure controller 17. The pressure is kept constant at 10 mTorr. Next, by supplying high-frequency power of 13.56 MHz to the electrode 12, low-temperature plasma is generated in the space containing the base material 13, that is, the space between the electrode 12 and the earth electrode 14, and the mixture of chlorine and boron chloride is generated. The gases are excited electrically, turning them into a low-temperature plasma state and making them active. By this operation, the aluminum 10-page minilam film on the substrate 13 is etched by the excited active gas. Here, during the etching, the excited state gas that was not used effectively, the unexcited mixed gas of chlorine and boron chloride, and the reaction product gas that was generated as a result of dry etching, the inside of the connecting part 19a. After passing through the vacuum pump 16 and being further treated by the exhaust gas treatment means 18, it is discharged into the atmosphere.

Here, an airtight cover 19 is provided on the outer periphery of the connecting member 19a.
b is arranged, even if the connecting member 19a is corroded by the transport gas and a hole is formed, the transport gas will not leak into the atmosphere. Furthermore, in this embodiment, the connecting member 1
The space between the cover 9a and the cover 19b is filled with nitrogen gas.
It was sealed at 6 atmospheres, and the pressure change was detected by a pressure sensor 20 and fed back to the control system of the main body of the device.

Therefore, if the connecting member 19a is corroded by the transport gas and a hole is formed in the connecting member 19a, the pressure state of the space between the connecting member 19a and the cover 19b changes immediately. This pressure change can be detected by the pressure 11b/force sensor 2o, and the safety circuit of the device control system can be operated, thereby improving the safety of the device.

Furthermore, whether the hole in the connecting member 19a is between the vacuum container 11 and the vacuum pump 16 or between the vacuum pump 16 and the exhaust gas treatment means 18
By displaying the pressure sensor, it is possible to easily discover whether there is a gap between the

Incidentally, even if a hole is formed in the cover 19b due to mechanical impact, for example, the connecting member 19a and the cover 1
Since the pressure between 9b and 9b is above atmospheric pressure, (
In this example, nitrogen gas atmosphere 1. ei snake/cni
) It can be detected by detecting a change in the indicated value of the pressure sensor 2o.

As described above, according to this embodiment, the vacuum container 11, the electrode 12 capable of generating low-temperature plasma, the vacuum pump 16, the exhaust gas treatment means 18, and at least a portion of the gas transporting portion are made of a flexible tube. The connecting member 19a has at least one airtight and flexible cover 19b on the outer periphery of the connecting member 19a.
By providing a pressure sensor 20 that detects a change in pressure in the space between the connecting member 19a and the cover 19b,
Even if the flexible tube part a is corroded by the transport gas, the transport gas will not leak, so the safety and maintainability of the device can be greatly improved.

In this embodiment, a case is described in which the connecting member 19a between the vacuum container 11 and the vacuum pump 16 and the connecting member 19a between the vacuum pump 16 and the exhaust gas treatment means 18 both require flexibility. However, for example, if a gas adsorption trap or the like is provided on the gas transport route and the exhaust gas treatment means 18 is not required, or the connection between the vacuum pump 16 and the exhaust gas treatment means 18 does not require flexibility and may be fixed. In some cases, the present invention may be applied to the section between the vacuum container 11 and the vacuum pump 16.

Similarly, if flexibility is not required in the connection between the vacuum container 11 and the vacuum pump 16, the present invention may be applied to the section 13' between the vacuum pump 16 and the exhaust gas treatment means 18.

In this example, the pressure sensor 2o is used to detect a change in the pressure state between the connection member 19a and the cover 19b, thereby detecting whether or not there is a hole in the flexible tube portion of the connection member 19a. However, a sensor such as a gas analyzer or a gas leak detector may be applied to detect the gas composition between the connecting member 19a and the cover 19b. It suffices if a change in the state of the space is detected.

Furthermore, in this embodiment, the pressure sensor 2o located between the vacuum container 11 and the vacuum pump 16 and the pressure sensor 20 located between the vacuum pump 16 and the exhaust gas treatment means 18 are the same; It may also be something with performance.

In this example, a dry etching apparatus was used for etching the aluminum film on the base material 13, but the base material 13 was maintained at an appropriate temperature of 100° C. to 500° C. by heating means, and the deposition was performed using a dry etching device. It can also be used as a plasma CVD apparatus for depositing a silicon nitride film on the base material 13 by supplying a compound gas containing the compositional elements of the desired film, for example, a mixed gas of monosilane (SiH) and ammonia (NH3). good. □
Effects of the Invention As described above, the present invention has an airtight structure in which at least a portion of the outer periphery of a connecting member for gas transportation, which airtightly connects a vacuum container and a vacuum pump, and a vacuum pump and an exhaust gas treatment means, is made of a flexible tube. By providing a cover with flexibility and flexibility, and further providing a means for detecting changes in the state between the connecting member and the cover, the safety of the equipment is improved by preventing the transport gas from leaking outside the gas transport path. The ease of maintenance can be greatly improved.

[Brief explanation of the drawing]

Fig. 1 is a schematic front sectional view of a vacuum device according to a first embodiment of the present invention, and Fig. 2 is a schematic front sectional view of a conventional vacuum device.
□Schematic front sectional view. 11... Vacuum container, 12... Electrode, 1
3...Base material, 16...Vacuum pump, 1
8...Exhaust gas treatment means 15' (--stage, 19...pipe, 19a...connecting member, 19b...cover, 20... ...Pressure sensor. Name of agent: Patent attorney Toshio Nakao and 1 other person + 2
-'t&f3-11 base

Claims (1)

[Claims] A vacuum container capable of maintaining a vacuum state, a vacuum pump that evacuates the vacuum container, an electrode to which high-frequency power or DC power is supplied and generates low-temperature plasma in the vacuum container, and a plasma discharged from the vacuum pump. A vacuum device comprising: an exhaust gas treatment means for treating gas; and a connection member for gas transport that airtightly connects the vacuum container, the vacuum pump, and the vacuum pump and the exhaust gas treatment means; A portion of the connection member is made of a flexible tube, and a cover having airtightness and flexibility is provided on the outer periphery of at least the portion of the connection member that is made of the flexible tube, and the condition of a sealed space between the connection component and the cover is further provided. A vacuum device characterized by comprising means for detecting a change.