JPH0827569A - Process device, surface treating method and gas feeding piping system - Google Patents

Abstract

PURPOSE:To feed gas of a high purity without using a large scale gas refining device and special piping by mounting piping systems introducing process gas by >= two pieces in parallel. CONSTITUTION:In the device in which gaseous Ar is fed from a cylinder 1 to a process chamber 5 through a gas flow rate controller 3, immediately before the chamber 5, piping systems introducing gas are mounted by >=2 pieces in parallel, and the pipings themselves are imparted with a function of removing impurities. For example, gas refining pipings 4a and 4b absorbing impurities such as water, carbon dioxide, oxygen or the like in the gas are mounted as shown in the figure by using valves 6 to 8. Thus, a large scale gas refining device and piping subjected to special treatment are unnecessitated, general SUS piping is made usable for piping 2a from a gas cylinder 1, and in the case where treatment such as film forming is not executed, the need of flowing gas to the piping systems is eliminated. Moreover, the treatment in which, while impurities in the gas are removed by one piping, simultaneously, the other piping is heated to exhaust the absorbed impurities is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process apparatus, a surface treatment method, and a gas supply piping system, and particularly to an introduction gas for a thin film manufacturing apparatus such as a sputtering or ion plating method which utilizes plasma ions due to a gas discharge phenomenon. To improve the purity of.

[0002]

2. Description of the Related Art In a sputtering thin film manufacturing apparatus, impurities such as water, nitrogen and oxygen are present in Ar gas of a cylinder, and among them, water is present at a concentration of about 150 ppb. There is a problem that these impurities are taken into the inside of the film during the film formation by sputtering, and the characteristics of the film are significantly deteriorated.

Therefore, conventionally, a sputtering thin film manufacturing apparatus as shown in FIG. 3 has been used. In FIG. 3, 1 is a supply cylinder of Ar gas for sputtering, 2b
Is a special pipe that has been treated to prevent degassing from the inner wall, such as oxidation passivation film treatment, 3 is a gas flow rate regulator, 4с is a large-scale gas purification device for removing impurities such as water and oxygen in the gas, Reference numeral 5 is a film forming chamber, and 6 is a valve.

In the conventional thin film manufacturing apparatus, it was necessary to connect an expensive and large-scale gas purification apparatus as shown in FIG. 3 in order to remove impurities. Further, it is necessary to periodically perform work for regenerating the impurity removing ability of the gas purifier, and during this time, there is a problem that gas supply to the film forming chamber must be stopped.

Further, in the course of introducing the further purified gas to the film forming chamber, in order to prevent contamination due to the release of the impurity gas from the inner wall of the pipe, it is necessary to use an expensive oxidative smoothing pipe.

Moreover, in order to actually form a film, it is necessary to carry out baking for 30 hours or more while continuously flowing Ar gas into this pipe, and after film formation, the Ar gas is accumulated in the pipe so that the baking is performed. In order to prevent the contamination of (1), it was necessary to always flow Ar gas.

As described above, the conventional thin film manufacturing apparatus has a problem that a large-scale gas purification apparatus which is expensive and complicated in operation and a special pipe are required, and further, a large amount of Ar gas is wasted.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a gas supply system capable of supplying high-purity gas without using a large-scale gas purification device and special piping. An object of the present invention is to provide a process device and a surface treatment method capable of forming a high-performance thin film, performing highly precise microfabrication and surface treatment.

[0009]

A process apparatus according to the present invention has at least one of piping systems for introducing a process gas.
Two or more process gas piping systems are installed in parallel.

The preferred form of the process apparatus of the present invention is
It is characterized in that the process gas can be independently introduced into each of the two or more pipe systems attached in parallel, and impurities in the process gas are removed by adsorption.

Furthermore, a desirable mode of the process apparatus of the present invention is a process apparatus in which a process gas is introduced into a process chamber from a gas supply source through a pipe, and at least one process gas of the process gases introduced into the process chamber is used. A gas purification pipe having a plurality of impurity gas removing capacities arranged in parallel and a switching valve for introducing a process gas into any of the gas purification pipes are provided in the middle of the pipe The process gas is introduced into the process chamber therethrough.

The surface treatment method of the present invention has a plurality of impurity gas removing capacities arranged in parallel in the middle of the piping of at least one of the process gases introduced into the process chamber from the gas supply source through the piping. A gas purifying pipe having the gas purifying pipe and a switching valve for introducing the process gas into any one of the gas purifying pipes are provided, and a process device in which the process gas is introduced into the process chamber through any of the gas purifying pipes is provided. In a surface treatment method for performing a surface treatment such as thin film formation on a substrate surface, while introducing a process gas into the process chamber while removing impurities in a first gas purification pipe of the plurality of gas purification pipes. In addition, the impurity gas adsorbed inside the other gas purification pipe is released and exhausted to the atmosphere to regenerate the impurity removing ability, and after a predetermined time, the valve is switched to switch the The gas introduced into the process chamber by introducing the gas into the process chamber through the gas purification pipe, and during this time, the impurities adsorbed inside the first gas purification pipe are released to the atmosphere for regeneration treatment. The surface treatment of the substrate is performed while continuously removing the impurities.

The gas supply pipe system of the present invention is a gas supply pipe system for introducing a process gas from a gas supply source into a process chamber through a pipe, and a plurality of impurities arranged in parallel in the middle of the pipe. It is characterized in that a gas purification pipe having a gas removing ability and a switching valve for introducing the gas into any one of the gas purification pipes are provided.

In the present invention, the outlet of the gas purification pipe is preferably connected to the film forming chamber via a valve. Further, it is preferable that the gas purification pipe is structured to be opened to the atmosphere through a valve and an exhaust pump, and the gas purification pipe preferably has a heating means for desorbing the impurity gas adsorbed inside. .

Further, it is desirable that the gas purification pipe is made of a material that adsorbs at least one of water, carbon dioxide, oxygen and nitrogen, and electropolished stainless steel is particularly preferable.

[0016]

In the process apparatus of the present invention, two or more pipe systems for introducing gas are installed in parallel just before the process chamber, and the pipes themselves have an impurity removing function. No need for specially treated piping. Further, since the pipe from the gas cylinder can be a general SUS pipe instead of the pipe having the special inner surface treatment, the facility cost can be significantly reduced.

Further, since impurities are removed immediately before the process chamber, it is possible to prevent the influence of contamination from the pipe from the gas cylinder to the process chamber. In addition, when a process such as film formation is not performed, it is not necessary to flow the gas through the piping system, and the gas can be saved.

Moreover, it is possible to perform a regeneration process in which impurities in the gas are removed by one pipe and at the same time, another pipe is heated to adsorb the adsorbed impurities by heating and exhausting, so that the gas is continuously introduced into the process without waste. can do. as a result,
For example, in a sputtering thin film manufacturing apparatus, it becomes possible to form a high-performance film having stable characteristics even when forming a film for a long time.

The gas purification pipe of the present invention adsorbs oxygen, carbon dioxide, water, nitrogen and the like, and is heated to desorb adsorbed impurities, so that any general metal material can be used. However, stainless steel is particularly preferable, and stainless steel whose inner surface with a high desorption rate of impurities is electrolytically polished is more preferable. The surface roughness (Rmax) of the inner surface of the electrolytically polished pipe is preferably 1 μm or less.

The impurity removing ability and the duration of the gas purification pipe of the present invention are related to the shape and number of the gas purification pipe, the flow rate of the process gas, the impurity concentration, etc. It is designed considering the impurity concentration. Therefore, the impurity concentration in the process gas is not particularly limited, but it is preferably applied to the process gas having an impurity concentration of 1 ppm or less in practical use in consideration of the regeneration cycle and the like. Further, a process gas of 300 ppb or less is particularly preferable. The process gas flow rate is, for example, 1
In the case of the / 4 "tube, a higher impurity removal capacity is exhibited at 1 liter / min or less.

As described above, the shape of the gas purification pipe is not particularly limited, and the inner diameter, the length, etc. may be appropriately determined according to the flow rate of the gas used, but in order to maintain the impurity removing ability for a longer time, For example, a small diameter pipe may be inserted into the gas purification pipe in a honeycomb shape.

The heating means of the present invention is not particularly limited as long as it can heat the inside of the gas purification pipe to about 100 ° C. or higher.

[0023]

【Example】

(Embodiment 1) FIG. 1 is a schematic view showing an example of a thin film manufacturing apparatus of the present invention. In FIG. 1, 1 is a supply cylinder of Ar gas for sputtering, 2a is a gas pipe which is not specially treated,
Reference numeral 3 is a gas flow rate controller, 4a and b are gas purification pipes having a function of removing impurities such as water and oxygen in the gas, 5 is a film forming chamber, and 6 to 10 are valves.

In FIG. 1, the gas purification pipes connected in parallel have a radius of 5 cm, a length of 64 cm, and an internal volume of 5 respectively.
A cylinder made of liter of stainless steel (SUS304),
The inner wall is electrolytically polished.

First, the valve 7a is opened, and the gas purification pipe 4a
Was heated to 140 ° C., and impurities adsorbed on the inner surface of the gas purification pipe were exhausted to the outside of the system. After 2 hours, the valve 7a was closed, heating was stopped, and cooling was performed. After cooling, set the flow rate regulator 3 to 100
The pressure was set to sccm, the valves 10, 9, 8a and 6a were opened, and Ar gas was introduced into the film forming chamber 5 at a flow rate of 100 sccm.

The results of measuring the impurity concentration in the Ar gas before and after the introduction of the introduction pipe 4a are shown in FIG. In FIG.
The vertical axis represents the concentrations of water (H ₂ O), oxygen (O ₂ ), and carbon dioxide (CO ₂ ) that are impurities in the Ar gas, and the unit is ppb. The horizontal axis INLET indicates before introduction of the gas purification pipe, and CH indicates after introduction. As shown in FIG. 2, before the gas purification piping, O ₂ , CO ₂ gas, and water were 30, 25, and 1, respectively.
Although 35 ppb was contained, after the gas purification pipe, each impurity was adsorbed on the inner wall of the cylinder, and O ₂ and CO ₂ were 1 ppb.
In the following, it was found that water, which is a main impurity, was also reduced to 4.5 ppb, and high-purity Ar gas was introduced into the film forming chamber. The effect of removing impurities in the gas purification pipe lasted 3 hours.

While Ar gas was being introduced into the film forming chamber through the gas purification pipe 4a, the heating / evacuating operation of the gas purification pipe portion 4b was performed in the same manner as 4a. Three hours after introducing the gas into the film forming chamber, the valves 8b and 6b are opened to open the valves 8a and
6a was closed and the gas purification piping was switched. When the impurity concentration in Ar gas was measured after the gas purification pipe,
Results similar to those in FIG. 2 were obtained.

As described above, by alternately switching the gas purification pipes and introducing the Ar gas into the film forming chamber, the high-purity Ar gas can be continuously introduced into the film forming chamber, and a high performance film can be obtained. It could be deposited for a long time.

In the present embodiment, when regenerating the gas purification pipe, the pipe was heated to evacuate the impurity gas adsorbed inside, but it is also possible to perform the regeneration treatment by heating while flowing Ar gas. Needless to say.

Example 2 The same treatment as in Example 1 was performed using a gas pipe made of SUS304, the inner surface of which was not electropolished, in the gas purification pipe portion. 200 ℃ for regeneration treatment, 3
It was confirmed that the same impurity removal as in Example 1 was achieved except that it took a long time to obtain a high-purity gas.

[0031]

As described above, according to the present invention, two or more gas purification pipes are installed in parallel immediately before the process chamber, and the gas purification pipes are operated alternately, thereby providing a large-scale gas purification device. High-purity gas can be continuously and efficiently introduced into the process chamber without using special piping, and the cost of the equipment can be reduced and the cost of the expensive process gas can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a thin film manufacturing apparatus of the present invention.

FIG. 2 is a graph showing the impurity concentrations in Ar gas before and after gas purification piping.

FIG. 3 is a schematic view showing a conventional sputtering thin film manufacturing apparatus.

[Explanation of symbols]

1 Sputtering Ar gas supply cylinder, 2a Pipe without special treatment, 2b Special pipe with degassing prevention treatment from inner wall, 3 Gas flow controller, 4a, 4b Gas purification pipe with a function of removing impurities, 4c Large-scale gas purifier for removing impurities, 5 process chambers, 6-10 valves.

Claims (19)

[Claims] 1. A process apparatus, wherein at least one process gas pipe system is installed in parallel among the process gas introduction pipe systems. 2. A structure in which a process gas can be independently introduced into each of the two or more pipe systems attached in parallel, and impurities in the process gas are removed by adsorption. Process device described. 3. A process apparatus for introducing a process gas from a gas supply source into a process chamber through a pipe, wherein at least one of the process gases introduced into the process chamber is arranged in parallel in the middle of the pipe. A gas purifying pipe having a plurality of impurity gas removing capacities, and a switching valve for introducing a process gas into any of the gas purifying pipes, and a process is performed in the process chamber through any of the gas purifying pipes. 3. Process device according to claim 1 or 2, characterized in that gas is introduced. 4. The process apparatus according to claim 3, wherein the outlet of the gas purification pipe is connected to the process chamber via a valve. 5. The process apparatus according to claim 4, wherein the gas purification pipe has a structure that is open to the atmosphere via a valve and an exhaust pump. 6. The process apparatus according to claim 4, wherein the gas purification pipe has a pipe diameter of ¼ inch to 10 inches. 7. The process apparatus according to claim 3, wherein the gas purification pipe adsorbs at least one of water, carbon dioxide, oxygen and nitrogen. 8. The gas purification pipe is made of stainless steel whose inner surface is electrolytically polished.
The process device described in 1. 9. The surface roughness of the inner surface of the stainless steel is
9. The process device according to claim 8, wherein the process device has a thickness of 0.1 μm or less. 10. The process apparatus according to claim 3, wherein the gas purification pipe has a heating unit for desorbing the impurity gas adsorbed inside. 11. The process apparatus according to claim 1, wherein the process apparatus is a sputtering apparatus or an ion plating apparatus. 12. The impurity gas concentration in the process gas is 300 ppb or less.
12. The process apparatus according to any one of 1 to 11. 13. The method according to claim 1, wherein the flow rate of the process gas is 1 liter / min or less.
The process apparatus according to claim 1. 14. A gas purification pipe having a plurality of impurity gas removing capacities arranged in parallel in the middle of a pipe of at least one kind of process gas introduced into a process chamber from a gas supply source through a pipe, A switching valve for introducing a process gas into any of the gas purification pipes is provided, and a thin film is formed on the substrate surface by using a process apparatus in which the process gas is introduced into the process chamber through any of the gas purification pipes. In a surface treatment method for performing surface treatment such as formation, while introducing a process gas into the process chamber while removing impurities in a first gas purification pipe of the plurality of gas purification pipes, another gas purification pipe Impurity gas adsorbed inside the pipe is released and exhausted to the atmosphere to regenerate the impurity removal ability, and after a predetermined time, the valve is switched to pass through the other gas purification pipe. Gas to the process chamber,
During this time, the impurities adsorbed inside the first gas purification pipe are released to the atmosphere to perform a regeneration process, thereby performing the surface treatment of the substrate while continuously removing the impurities in the process gas introduced into the process chamber. A surface treatment method characterized by the above. 15. A gas supply pipe system for introducing a process gas from a gas supply source to a process chamber through a pipe, the gas purifying having a plurality of impurity gas removing capacities arranged in parallel in the middle of the pipe. A gas supply pipe system comprising a pipe and a switching valve for introducing a process gas into any one of the gas purification pipes. 16. The gas purifying pipe has a structure that is open to the atmosphere via a valve.
5. The gas supply piping system according to item 5. 17. The gas supply piping system according to claim 15, wherein the gas purification piping adsorbs at least one kind or two or more kinds of water, carbon dioxide, oxygen and nitrogen. 18. The gas supply piping system according to claim 17, wherein the gas purification piping is made of stainless steel whose inner surface is electrolytically polished. 19. The gas supply pipe system according to claim 15, wherein the gas purification pipe has a heating unit for desorbing the impurity gas adsorbed inside.