JP3243562B2 - Inner surface treatment method for apparatus having space inside - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating an inner surface of an apparatus having a space inside a fluid storage tank or a chamber used in the field of semiconductor manufacturing.

[0002]

2. Description of the Related Art In a device or equipment such as a chamber constituting a semiconductor manufacturing apparatus, an inner surface of the apparatus is immobilized in order to prevent the apparatus from being damaged by a reactive gas used during semiconductor manufacturing or etching. That is used. Techniques for passivating the inner surface of semiconductor manufacturing equipment include treating the inner surface of the equipment by injecting a strong oxidizing liquid into the equipment, or treating the inner surface of the equipment by filling a strong oxidizing gas. are doing.

[0003]

However, in the conventional treatment of the inner surface of the device, a large amount of liquid or gas is required in accordance with the volume of the device. Is expensive. The present invention has been made in view of such a point, and an object of the present invention is to provide a technique for inexpensively and easily passivating the inner surface of a semiconductor manufacturing tool.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention comprises inserting an inflatable and deflated bag such as a balloon into an internal space of a device having a space therein, and connecting the inner surface of the device with the bag. After the space between the outer surface of the body is decompressed, gas is supplied into the bag to expand the bag inside the device to reduce the volume of the space between the inner surface of the device and the bag. The space is filled with ozone gas, or an inflatable and deflated bag such as a balloon is inserted into the internal space of a device having a space therein, and gas is supplied into the bag and the bag is inserted into the device. In a state where the volume of the space between the inner surface of the device and the bag body is reduced by expansion, ozone gas is injected to replace the inside of the space with ozone, and then the space is filled with ozone gas. It is characterized in that a passive film is formed by ozone.

[0005]

According to the present invention, a bag which can be inflated and contracted is inserted into the inside of the appliance in the interior space of the appliance having a space therein, and the bag and the appliance are expanded in the interior space of the appliance. Since the space between the inner surface is filled with ozone gas, the space volume in the gas cylinder is reduced,
The amount of ozone gas to be filled can be greatly reduced.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention, and FIG. 1 is a schematic diagram showing a case of processing a bell jar as an instrument used in the manufacture of semiconductors. Symbols in the figure
(1) is a bell jar as a device to be processed, (2) is a bell jar mounting substrate, and a support ring (4) for supporting and fixing a bag (3) described later protrudes from the upper surface of the substrate (2). At the same time, a gas supply passage (5) is opened in a substrate portion located inside the support ring (4), and a gas communication passage (6) is opened in a substrate portion located outside the support ring (4).
Is open.

[0007] The expansion gas supply path (5) has a flow path opening / closing valve.
(7) An inert gas such as nitrogen gas, carbon dioxide gas, argon gas, helium gas or the like or a gas stored in a gas storage container (not shown) is interposed with a compressor (8).
(3) is supplied.

On the other hand, the inner end of the gas communication passage (6) communicates with the inner space (9) of the bell jar (1), and the outer end thereof has a vacuum pump (1).
(0) and a gas exhaust passage (11)
It is connected to a gas supply path (13) communicating with (12).
Note that concentrated ozone gas is used as the processing gas, and reference numeral (14) in the figure denotes an ozone decomposer arranged in the gas discharge path (11).

The bag body (3) fixed to the support ring (4) is formed in a balloon-like shape so as to be inflatable and contractible. It is made of a material having a high ozone resistance such as ethylene and perfluoroelastomer, so that the material of the bag does not decompose or react even when exposed to ozone gas.

Next, a procedure for forming an oxidation passivation film on the inner surface of the bell jar will be described. First, the bell jar (1) is placed on the substrate so as to cover the bag (3) fixed to the support ring (4).
Fix to (2). Next, the inner space of the bell jar (1)
(9) is communicated with the gas discharge path (11) to evacuate (depressurize). When the evacuation is completed, the gas discharge path (11) is closed, and the expansion gas supply path (5) is opened, so that an inert gas such as nitrogen gas, carbon dioxide gas, argon, or helium is introduced into the bag body (3). Alternatively, supply air at a gauge pressure of 98 kPa and
(3) is expanded.

In the inner space (9) of the bell jar (1), a bag (3) is formed.
After the gas has sufficiently expanded, the expansion gas supply path (5) is closed and the gas supply path (13) communicating with the gas communication path (6).
Is opened, and the ozone gas in the processing gas storage container (12) is fed and supplied to the outside of the bag body (3) in the inner space (9) of the bell jar (1), and the gas supply path (13) is closed. With the ozone gas sealed state maintained, an oxidation passivation film is formed on the inner surface of the bell jar (1) with ozone gas, and the inner surface of the bell jar (1) is passivated. In this case, the passivation process is completed when the pressure fluctuation in the internal space (9) of the bell jar (1) is completely eliminated.

Next, the gas discharge passage (11) is opened to discharge the ozone gas in the bell jar (1). The discharged ozone gas is decomposed by the ozone decomposer (14) and released to the atmosphere. In addition, the gas supply path for expansion (5) is opened to open the bag (3).
, And remove the bell jar (1) from the substrate (2).

[0013] In the above procedure, the bell jar (1) in one pass
Although the inner wall surface has been passivated, the process of filling new ozone gas after the ozone gas is discharged and maintaining it for a predetermined time may be repeated several times. In addition, as a means for expanding the bag body (3) in the internal space (9) of the bell jar (1), the bag body (3) is pressurized and expanded using a compressor.
The self-pressure expansion may be performed at atmospheric pressure by utilizing the pressure difference inside the bag body caused by the decompression operation of the internal space (9).

In the above embodiment, a bell jar was described as an example of the equipment to be processed. However, the present invention is not limited to the case in which both ends of the end plate portion of the container used in semiconductor manufacturing and the cylinder body used in the chamber are opened. It can be used when passivating the inner surface of a member formed in a shape. This technique can also be applied to the inner surface treatment of a storage tank or a fermentation tank for storing foods and drinks and pharmaceuticals.

Further, in the above-described embodiment, after the space between the inner wall of the equipment to be processed and the inflatable and contractible bag inserted into the equipment is depressurized, gas is supplied to the bag to supply the gas to the bag. Although the body is inflated, the bag may be inflated by supplying gas to the bag without depressurizing the space between the inner wall surface of the device and the bag. in this case,
By opening the space to the outside through an ozone gas discharge path or the like used at the time of post-processing, the pressure in the space becomes equal to the external pressure (atmospheric pressure). By supplying a gas at a positive pressure, the bag body can be inflated, the space volume between the inner wall surface of the device and the bag body can be reduced, and the ozone gas supply pressure during the passivation process is also reduced to the gauge pressure. Can be supplied with a slight positive pressure.

[0016]

According to the present invention, an expandable / contractible bag is accommodated in the internal space of the device, and a processing gas such as ozone gas is introduced while the bag is inflated. Since the space volume of the device at the time is the gap between the bag body and the inner wall of the device, the space volume is reduced. As a result, the inner surface of the cylinder body can be processed with a small amount of processing gas.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a bell jar.

[Explanation of symbols]

1 ... bell jar, 3 ... bag, 9 ... space between the inner surface of the device and the outer surface of the bag.

Claims (8)

(57) [Claims] 1. An inflatable and deflated bag (3) such as a balloon is inserted into an internal space of a device (1) having a space inside, and the device (1) is inserted into the device (1).
After decompressing the space (9) between the inner surface of the bag and the outer surface of the bag (3), a gas is supplied into the bag (3) to remove the bag (3) from the device.
By expanding the space (9) between the inner surface of the device (1) and the bag (3) while reducing the volume of the space (9), the space (9) is filled with ozone gas. An inner surface treatment method for a device having a space inside, in which a passive film made of ozone is formed on the inner surface of the device (1). 2. The method according to claim 1, wherein the step of evacuating the device (1), the step of expanding the bag (3), and the step of supplying ozone into the gas cylinder (1) are repeated several times in one cycle. An inner surface treatment method for a device having a space inside. 3. The method according to claim 1, wherein the gas supplied to the inside of the bag (3) is an inert gas. 4. The method according to claim 1, wherein the outer surface of the bag is formed as an ozone-resistant surface. 5. An inflatable and shrinkable bag body (3) such as a balloon is inserted into an internal space of a device (1) having a space inside, and the bag body (3) is inserted.
The bag (3) is expanded in the device (1) by supplying gas into the space (9) between the inner surface of the device (1) and the outer surface of the bag (3).
The space (9) is replaced with ozone gas in a state where the volume of the device (1) is reduced, and then the space (9) is filled with ozone gas to form a passive film of ozone on the inner surface of the device (1). Inner surface treatment method for a device having a space inside. 6. The method according to claim 5, wherein the inflating step of the bag (3), the step of replacing ozone in the instrument (1), and the step of supplying ozone into the instrument (1) are repeated as a cycle several times. An inner surface treatment method for a device having a space inside as described above. 7. The method according to claim 5, wherein the gas supplied into the bag (3) is an inert gas. 8. The method according to claim 5, wherein an outer surface of the bag body (3) is formed on an ozone-resistant surface.