JPH01270933A - Device for treatment under reduced pressure - Google Patents

Abstract

PURPOSE:To make it possible to easily detect the completion of cleaning and reduce the time required therefore by providing a means to exhaust air under reduced pressure from the inside of a device, a means to restore atmospheric pressure therein, and a means to measure dust concentration in the device wherein the pressure has been restored to atmospheric pressure. CONSTITUTION:In a device 1 to treat samples under reduced pressure, the pressure therein is reduced by exhausting air therefrom by means of a means 11 and also restored to atmospheric pressure by means of a means 10. And further, the dust concentration in the device 1, the inside pressure of which has been restored to atmospheric pressure, is measured by means of a dust concentration measurement equipment 17. As a result, completion of cleaning of the inside of the device 1 can be easily detected and time required therefor can be made shorter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reduced pressure processing apparatus, and more particularly to a reduced pressure processing apparatus in which the inside of the apparatus is cleaned by purge and flow.

[Conventional technology]

Plasma processing equipment such as dry etching equipment generally consists of a plasma processing chamber, a buffer chamber for transportation, and a load lock chamber, but the plasma processing chamber contains ebbed particles and deposited effluent components, so the inside of the chamber is are contaminated with these dusts, and the bubble chamber and load lock chamber, which communicate as a vacuum chamber, are also contaminated during transportation. As a cleaning technique for such processing chambers and vacuum chambers, for example, a technique has been proposed in which an exhaust system and a leak system are provided and the systems are operated alternately for cleaning, as described in Japanese Patent Laid-Open No. 60-91641. There is.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, in order to confirm the completion of cleaning, it is necessary to measure the number of foreign substances attached to the sample after being transported using a face plate defect device, and repeat the measurement until the target value is achieved. Therefore, there is a problem in that the time required for cleaning becomes large.

The purpose of the present invention is to easily detect the end of cleaning;
The object of the present invention is to provide a decompression processing device that can reduce the time required for the processing.

[Means to solve the problem]

The above object is to provide a depressurization processing device equipped with a means for depressurizing and exhausting the inside of the device, a means for returning the inside of the device to atmospheric pressure, and a means for measuring the dust concentration inside the device after being returned to atmospheric pressure. This is achieved by doing this.

[For production]

BACKGROUND ART In a reduced pressure processing apparatus, for example, in a plasma processing apparatus, the inside of a plasma processing chamber, a bubble chamber for transportation, a load lobster chamber, etc. is evacuated to a reduced pressure by operation of a reduced pressure bi-air means. Thereafter, the inside of the apparatus is returned to atmospheric pressure by the purge means. The dust concentration inside the apparatus, which has been returned to the atmosphere, is measured by a dust concentration measuring means, for example, by irradiating the floating point with an H6-Ne laser and detecting the scattered light from the dust. Such operations are repeated and the above! The cleaning operation is completed when the measured dust concentration within 1ltW becomes equal to or less than the target value.

Therefore, it is no longer necessary to measure the number of foreign substances attached to the sample after transportation, as in the conventional method, for each of the above-mentioned operations.

〔Example〕

The case where the present invention is applied to a load lock chamber will be described below as an embodiment of the present invention with reference to FIGS. 1 and 2. The load lock chamber 1 is composed of a lower lid 2, an upper lid 3° chamber 4, and a lower lid 2. An O-ring 5 is provided between the upper lid 3 and the chamber 4 so that the upper lid 3 can be raised and lowered independently using an air cylinder or the like. When the lower lid 2 is lowered from the state shown in FIG. 1, the load lock chamber 1 communicates with a buffer chamber (not shown) or a process chamber (not shown), allowing wafers to be transferred. - The lid 3 is provided with an up-and-down mechanism 6 for transferring the wafer holder and an O-ring 7 for guiding it. Glue to chamber 4-
A leak gas supply system 10 is provided, and a leak gas supply system 10 is provided. Connected to the exhaust system 11, a pipe 12 leading to the exhaust system 11 includes an atmosphere detector 13. which detects whether the inside of the load lock chamber 1 is at atmospheric pressure or higher and is in a vacuum. A vacuum detector 14 is attached. Further, a sampling boat 15 is provided on the upper lid 3I, and a dust concentration measurement n17 for measuring the dust concentration in the gas sampled from inside the load lock chamber 1 via the solenoid valve 16 is provided. Note that the magnetic valve 16 is operated by a signal from the atmospheric detector 13.

In Fig. 2, the upper lid 3 and lower lid 2 of the load lock chamber l are
Cleaning is carried out by performing a leak operation while performing an exhaust operation while the air is lowered and raised respectively. Further, in this state, the leak gas flow cover is adjusted so that the atmospheric pressure detector 13 does not operate, the solenoid valve +6 does not operate, and the load lock chamber 1 and the dust concentration fAl regulator 17 are not communicated. After that, when the exhaust operation is stopped while continuing the leak operation, the pressure inside the load lock chamber 1 becomes higher than atmospheric pressure, and the atmospheric pressure is detected W 13 , the solenoid valve 16 is activated, and the leak gas in the load lock chamber 1 is drawn up from the sampling port b. The dust-containing gas thus collected is guided to a dust concentration measuring device 17. Then, the dust concentration of the gas sampled within a predetermined period of time is displayed in Dust@degree_en_determination1ii17. If the value is below the target value, cleaning will end, but
If it is above the target value, the cleaning and dust concentration measurement operations are repeated until it becomes below the target value.

In addition, the target value for the dust concentration in the load lock chamber l is Dust! The relationship between the number of foreign substances attached at one time, exhaust, and leak is determined and set in advance through experiments.

According to this embodiment, unlike the conventional method, it is not necessary to measure the number of foreign substances attached to the sample after being transported for each cleaning operation, so the end T of cleaning the load lock chamber can be easily detected. The time required for this can be shortened. In addition, the time required to clean the load lock chamber can be shortened, improving the operation rate of the load lock chamber.
Sloop can be greatly improved.

In addition to the embodiment of the Kouki, the dust concentration in the load lock chamber may be directly measured without sampling the gas in the room. When sampling room gas, it is preferable to sample the gas in the area with the most dust in the load lock chamber.

〔Effect of the invention〕

According to Book 5, it is possible to easily detect the end of cleaning inside the vacuum processing apparatus, and the time required for this can be shortened.

[Brief explanation of the drawing]

1g1 is a device configuration diagram of a load lock chamber portion of a decompression processing apparatus according to an embodiment of the present invention, and FIG. 2 is a cleaning operation diagram in FIG. 1. 1...Load lock chamber, lO...Leak gas supply system, 11...Exhaust system, 13...
...Atmospheric detector, 15...Sampling boat, 16...Solenoid valve, 17...Dust concentration measuring device Fig. 2

Claims (1)

[Claims] 1. In an apparatus for processing a sample under reduced pressure, means for evacuating the inside of the apparatus under reduced pressure, means for returning the inside of the apparatus to atmospheric pressure, and means for measuring the dust concentration in the apparatus after being returned to atmospheric pressure. A decompression processing device characterized by comprising: