JPH0633875A - Cryopump - Google Patents

Abstract

PURPOSE:To alternately regenerate cryopanels and permit the continuous operation by partitioning the inside of a pump case to a plurality of trap chambers by a cold head and arranging each cryopanel, heating means, and each exhaust means in each trap chamber. CONSTITUTION:Cryopanels 35a and 35b arranged on a plurality of trap chambers 31a and 31b are cooled by cooling a cold head 34. An intake port of one trap chamber 31a is closed by one opening/closing means 30a, and one cryopanel 35a is heated by one heating means 36a, and the surface accumulated articles are gasified. Then, gas is discharged outside the trap chamber 31a by an exhaust means 37, and one cryopanel 35a ia regenerated. During the regeneration of one cryopanel 35a, the other cryopanel 35b arranged in the other trap chamber 31b condensation-solidifies the base body particles on the surface and makes the other trap chamber 31b vacuum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cryopump, and more particularly to a cryopump which can be continuously operated for a long time.

[0002]

2. Description of the Related Art Next, a conventional cryopump will be described with reference to FIG. FIG. 2 is a schematic side sectional view of a conventional cryopump.

As shown in FIG. 2, a conventional cryopump has a cylindrical pump case 21 connected to a vacuum chamber 11 or the like via a vacuum valve 12 and a refrigerator 23 by compressing helium gas.
To the compressor case 21, a cold head 24 disposed inside the pump case 21 to expand the helium gas supplied from the refrigerator 23 inside to cool the cryopanel 25 fixed to the surroundings, and the pump case 21. It was configured to include a heater 26 that is disposed inside and can heat the cryopanel 25.

Therefore, the roughing pump 13 is used for the vacuum chamber.
After depressurizing the inside of 11 and the inside of pump case 21, by operating compressor 22 to cool cryopanel 25 via cold head 24, the gas is condensed and solidified on the surface of this cryopanel 25, and the cryopanel 25 is collected. (Hereinafter referred to simply as “condensation and solidification”), and an extremely high vacuum (pressure is 10 ⁻⁹ Torr
Below)

[0005]

By the way, as described above, the cryopump is a storage pump, that is, the surface of the cryopanel 25 is condensed and solidified (or condensed and solidified and sorbed) with gas molecules to form a vacuum. It is what you create.

Therefore, in the cryopump, when a deposit (not shown) formed by condensation and solidification of gas molecules on the surface of the cryopanel 25 reaches a limit amount, the cryopanel 25 is regenerated, that is, the deposit is removed. It is indispensable to gasify the gas and release it to the atmosphere outside the pump case 21, for example, via the roughing pump 13.

Of course, the valve 14 is opened when the roughing pump 13 is operated. Even if the cryopanel 25 is forcibly heated by the heater 26, it usually takes several hours to regenerate the cryopanel 25.
(Time from stop of cryopump to re-operation) is required.

[0008] Such a regeneration cycle is determined by many factors such as the operating time of the cryopump and the volume of the vacuum chamber 11, but in many cases, it is normally performed every one week to ten days. Is.

Therefore, the vapor deposition apparatus and the like constructed by adopting such a cryopump had to be suspended for several hours every one week to ten days. The present invention has been made to solve such a problem, and an object thereof is to provide a cryopump capable of continuous operation for a long time.

[0010]

As shown in FIG. 1, the above-mentioned object is to divide the inside into a first trap chamber 31a and a second trap chamber 31b by a cold head 34, A pump case in which the inlet of the trap chamber 31a is opened and closed by the first opening / closing means 30a, and the inlet of the second trap chamber 31b is opened and closed by the second opening / closing means 30b.
31, the first and second cryopanels 35a and 35b fixed to the respective side surfaces of the cold head 34 exposed in the first and second trap chambers 31a and 31b, and the first and second cryopanels 35a. It is characterized in that it comprises first and second heating means 36a, 36b capable of independently heating the respective Achieved by cryopump.

[0011]

The cryopump of the present invention can be regarded substantially as being constituted by two cryopumps which can be operated independently.

That is, the first cryopanel 35 which cools the cold head 34 and is disposed in the first trap chamber 31a.
a and the second cryopanel 35b provided in the second trap chamber 31b are cooled, and then the first trap chamber 31b is cooled.
The intake port of 31a is closed by the first opening / closing means 30a, and the first cryopanel is opened by the first heating means 36a.
The cryopanel 35a is regenerated by heating 35a to gasify the deposits on the surface of the first cryopanel 35a and discharging the gas by the exhaust means 37 to the outside of the first trap chamber 31a, for example, the atmosphere. be able to.

Even during the regeneration of the first cryopanel 35a, the second cryopanel 35b arranged in the second trap chamber 31b condenses and solidifies gas molecules on its surface,
The trap chamber 31b can be evacuated.

This is the case with the first cryopanel 35.
a to the second cryopanel 35b and the first trap chamber 31
Paraphrase a to the second trap chamber 31b, paraphrase the second cryopanel 35b to the first cryopanel 35a, and paraphrase the second trap chamber 31b to the first trap chamber 31a. It is possible.

Therefore, in the cryopump of the present invention, since the first cryopanel 35a and the second cryopanel 35b can be regenerated alternately, continuous operation for a long time is possible.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cryopump according to an embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a schematic side sectional view of a main part of a cryopump according to an embodiment of the present invention.

In the present specification, the same parts, the same materials and the like are designated by the same reference numerals throughout the drawings. As shown in FIG. 1, a cryopump according to an embodiment of the present invention includes first and second vacuum valves 30 which are opening / closing means.
The first and second trap chambers 31a and 31b are partitioned by a and 30b and a flat cold head 34, and the intake port A of the first trap chamber 31a is opened and closed by the first opening / closing means 30a. And the inlet B of the second trap chamber 31b is opened and closed by the second opening / closing means 30b.
As with the conventional cryopump compressor 22 described with reference to FIG. 2, a compressor 32 that compresses helium gas and sends it to the refrigerator 33; The first trap chamber 31a and the second trap chamber 31b are separated from each other, and the helium gas supplied from the refrigerator 33 is internally expanded to cool the cold head 34;
And the first and second cryopanels 35a, 35b fixed to the respective side surfaces of the cold head 34 exposed in the second and third trap chambers 31a, 31b, and the first and second trap chambers 31a, 31b.
The first and second cryopanels 35a, 35 are arranged on the 31b.
First and second heating means capable of heating b independently of each other
36a, 36b and a roughing pump 37, which is an exhausting means capable of separately exhausting the insides of the first and second trap chambers 31a, 31b, through the first and second vacuum valves 30a, 30b. The inside of the vacuum chamber 11 connected with each other is set to an ultrahigh vacuum.

In the cryopump according to the embodiment of the present invention constructed as described above, the refrigerator 33 is operated to cool the cold head 34, and the first head is disposed in the first trap chamber 31a.
If the first cryopanel 35a and the second cryopanel 35b arranged in the second trap chamber 31b are cooled, the first and second cryopanels 35a, 35b will be replaced by the first and second vacuum valves 30a, 30b. From the first and second trap chambers respectively
The gas existing in the vacuum chamber 11 that has flowed into the chambers 31a and 31b is condensed and solidified to make the inside thereof an ultrahigh vacuum.

Then, for example, the first cryopanel 35a
When it becomes necessary to reproduce, the reproduction can be performed by the following procedure. First, the first vacuum valve 30a
This closes the intake port A of the first trap chamber 31a and activates the heating means 36a to activate the first cryopanel 35.
a is heated, and the deposit deposited on the surface of the first cryopanel 35a is gasified.

Then, if the gas in the first trap chamber 31a is discharged to the atmosphere, for example, by the roughing pump 37 operated before and after the operation of the heating means 36a, the cryopanel 35a.
Is played.

Even during the regeneration of the first cryopanel 35a, the second cryopanel 35b arranged in the second trap chamber 31b condenses and solidifies the gas molecules on the surface thereof to exhaust the vacuum chamber 11. Of course, it continues.

At this time, it is obvious that the first valve 38a is open and the second valve 38b is closed. This means that the first cryopanel 35a is referred to as the second cryopanel 35b, the first trap chamber 31a is referred to as the second trap chamber 31b, and the second cryopanel 35b is referred to as the first cryopanel 35b. The second trap chamber 31b is attached to the cryopanel 35a of the first trap chamber 31b.
Each can be paraphrased like a.

Therefore, in the cryopump of the present invention, since the first cryopanel 35a and the second cryopanel 35b can be regenerated alternately, continuous operation for a long time is possible.

[0024]

As described above, the present invention makes it possible to provide a cryopump capable of continuous operation for a long time.

Therefore, if the cryopump of the present invention is used to construct a vacuum vapor deposition apparatus or the like, its operating rate will be improved.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a main part of a cryopump according to an embodiment of the present invention,

FIG. 2 is a schematic side sectional view of a conventional cryopump.

[Explanation of symbols]

11 is a vacuum tank, 12, a vacuum valve, 13 is a roughing pump, 14 is a valve, 21 is a pump case, 22 is a compressor, 23 is a refrigerator, 24 is a cold head, 25 is a A cryopanel, 26 is a heater, 30a and 30b are first and second vacuum valves (first and second vacuum valves).
Opening / closing means), 31 is a pump case, 31a and 31b are first and second trap chambers, 32 is a compressor, 33 is a refrigerator, 34 is a cold head, and 35a and 35b are first. And a second cryopanel, 36a and 36b are first and second heaters (heating means), 37 is a roughing pump (exhaust means), and 38a and 38b are first and second valves, respectively. Show.

Claims (1)

[Claims] 1. The inside is divided into a first trap chamber (31a) and a second trap chamber (31b) by a cold head (34), and an intake port of this first trap chamber (31a) is a first trap chamber (31a). A pump case (31) that is opened and closed by the first opening and closing means (30a) and the intake port of the second trap chamber (31b) is opened and closed by the second opening and closing means (30b); First and second cryopanels (35a, 35b) fixed to respective side surfaces of the cold head (34) exposed in the second trap chambers (31a, 31b), and the first and second cryopanels First and second heating means (36a, 36b) capable of independently heating (35a, 35b)
And a cryopump (37) capable of separately evacuating the first and second trap chambers (31a, 31b).