JP2000223550A - Method of processing substrate in vacuum processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent contamination of a product due to occurrence of contaminant, residual gas and the like by processing a substrate within a cassette in any vacuum processing chamber, dry-cleaning the inside of the vacuum processing chamber and processing a substrate within a cassette in the dry- cleaned vacuum processing chamber. SOLUTION: A load-lock chamber 5 as vacuum processing chamber is evacuated to a prescribed pressure after closing a separate valve 12a, and then a substrate 20 is carried to each of etching chambers 11a, 11b and 11c by means of a vacuum carrier provided in a carrying chamber 16 after opening a separate valve 12b. The substrate 20 carried in each of the etching chambers 11a, 11b and 11c is etched under a prescribed condition. Subsequently, the load-lock chamber 5 is dry-cleaned, a substrate 20 in another cassette 1a not yet processed is carried in the dry-cleaned load-lock chamber 5, and the substrate 20 in the cassette 1a is processed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vacuum processing apparatus and a vacuum processing method for a substrate, and more particularly to a vacuum processing having a plurality of vacuum processing chambers and a vacuum processing method for a substrate using the same.

[0002]

2. Description of the Related Art In a vacuum processing apparatus such as a dry etching apparatus, a CVD apparatus or a sputtering apparatus, a plurality of predetermined substrates to be processed are housed in a substrate cassette as one unit (generally called a lot). It is a general vacuum processing apparatus transport system and its operation method that the efficiency of production is improved by putting the processed substrates into the substrate cassette and collecting the processed substrates in the same unit.

However, in the above vacuum processing apparatus, particularly in an apparatus utilizing a reaction by an active gas such as a dry etching apparatus and a CVD apparatus, a reaction product adheres and accumulates in a processing vessel as the processing is performed. Often, problems such as deterioration of vacuum performance, increase of dust, and decrease in the level of an optical monitor signal occur, and in order to avoid such problems, an operation of periodically cleaning the inside of the processing container is performed. Cleaning work includes so-called wet cleaning, which wipes off deposits with an organic solvent, etc., and dry cleaning, which uses active gas or plasma to decompose the deposits. From the viewpoint of workability and efficiency, dry cleaning is superior. These features are becoming essential as production lines become more automated.

An example of a transfer system for a vacuum processing apparatus having such a function is the apparatus disclosed in Japanese Utility Model Laid-Open No. 63-127125.

[0005]

Problems to be Solved by the Invention
In the apparatus disclosed in Japanese Patent No. 127125, a dummy wafer housed in a vacuum preparatory chamber in advance is loaded into the processing chamber to perform plasma cleaning of the processing chamber, and after the plasma cleaning is completed, the dummy wafer is transferred to the vacuum preparatory chamber by the transfer means. It has been made to return. For this reason, there is a problem that the vacuum spare chamber for accommodating the dummy wafer requires a large volume and requires a transfer mechanism dedicated to the dummy wafer, which complicates the apparatus.

Further, in order to continue the normal processing after the dummy wafer once used for the plasma cleaning is returned to the vacuum preparatory chamber, the used dummy wafer and the normal processing are received in the vacuum preparatory chamber. The unprocessed wafer to be mixed is mixed, which is not preferable from the viewpoint of product contamination.

An object of the present invention is to solve the above problems,
Eliminate product contamination due to garbage and residual gas,
It is an object of the present invention to provide a vacuum processing for realizing high production efficiency and a high product yield and a vacuum processing method for a substrate using the same.

[0008]

According to the present invention, there is provided a transfer chamber connected to a plurality of vacuum processing chambers for vacuum processing a substrate to be processed one by one, and a plurality of transfer chambers capable of storing a plurality of substrates to be processed or processed. A cassette table on which a cassette is placed in the atmosphere, and a lock chamber for loading the substrate to be processed from the cassette in the atmosphere and unloading the substrate to any vacuum processing chamber via the transfer chamber. And another lock chamber for carrying the processed substrate from one of the vacuum processing chambers through the transfer chamber and unloading the processed substrate to the cassette in the atmosphere, and the cassette in the atmosphere. An atmosphere transfer device that transfers the substrate to be processed or the processed substrate one by one to or from any of the lock chambers. After serial treated with either vacuum processing chamber, the vacuum processing chamber to dry cleaning, a vacuum processing chamber that the dry cleaning, characterized by treating the substrate in the cassette.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a vacuum processing apparatus according to the present invention.
FIG. 3 is a diagram illustrating an application to an apparatus that performs a dry etching process on a semiconductor wafer.

The apparatus is provided with a plurality of (usually 25) wafers for supplying an object to be processed to the apparatus in a state where the unprocessed wafers are stored, and storing and processing the processed wafers at the original position again. A plurality of cassettes 1a capable of storing wafers,
1b and 1c, on which the cassettes 1a, 1b, 1c are mounted and always fixed on a horizontal or near-horizontal plane without changing the position and attitude for determining the position of introduction / discharge to the apparatus. Cassette table 2a, 2 fixed in position
b, 2c, a load lock chamber (substrate receiving chamber) 5 for introducing a wafer into a vacuum atmosphere, which is equipped with a vacuum exhaust device and a gas introducing device (not shown), and an unload lock chamber for taking the wafer into the atmosphere ( Substrate unloading chamber) 6.
Etching 11 for performing etching process on wafer
(11a, 11b, 11c), an isolation valve 12 capable of separating them airtightly, and a load lock chamber (substrate receiving chamber) 5 / unload lock chamber (substrate unloading chamber) 6 and cassettes 1a, 1b, 1c. Between the load lock chamber (substrate receiving chamber) 5 / unload lock chamber (substrate unloading chamber) 6 and the cassettes 1a, 1b, 1c provided with a robot having X, Y, Z and θ axes. And a first transfer device 13 for sending and receiving wafers.

As an operation of the apparatus, first, cassettes 1a and 1b storing unprocessed wafers are supplied from a stocker (not shown) to the apparatus by a robot or an operator, and are mounted on the cassette tables 2a and 2b. At this time, since the cassette tables 2a and 2b are on the same horizontal plane, it is possible to simplify the operation of supplying the cassette, and it is easy to respond to automation of the production line. On the other hand, the cassette table 2
On c, a cassette 1c containing dummy wafers is placed.

The apparatus is capable of recognizing the production information given to the cassette by itself, based on information sent from a higher-level control device, or by a command input by an operator.
The wafer can be processed by any of the methods.

An unprocessed wafer (substrate) 20 stored in the cassette 1a is extracted by the first transfer device 13, and a load lock chamber (substrate receiving device) disposed on the opposite side of the first transfer device 13 from the cassette 1a. To chamber 5) Isolation valve 12a
Carry in through. At this time, the wafer (substrate) 20
It may be stored in any place in the cassette 1a. After the wafer (substrate) 20 enters the load lock chamber (substrate receiving chamber) 5 from the isolation valve 12a and exits the unload lock chamber (substrate unloading chamber) 6 from the isolation valve 12b, the atmosphere outside the apparatus is completely complete. Because it is in a state of being cut off,
A partition is provided between the isolation valves 12a and 12b, and the cassette tables 2a and 2b and the cassettes 1a and 1b mounted thereon are provided.
In addition, only the first transfer device 13 can be placed in the clean room where the cleanliness is high, and the rest can be placed in the maintenance room where the cleanliness is low. After closing the isolation valve 12a, the load lock chamber (substrate receiving chamber) 5 is evacuated to a predetermined pressure by an exhaust device (not shown), and then the isolation valve 12b is opened to transfer the wafer (substrate) 20. The wafer is transferred to each of the etching chambers 11 (11a, 11b, 11c) by a vacuum transfer device (not shown) provided in the chamber 16, and is placed on each of the sample tables 8 (8a, 8b, 8c).

Each of the etching chambers 11a, 11b, 11
In c, an isolation valve 12a ', 12b', 12c '(not shown) is provided between the transfer chamber 16 and the transfer chamber 16 so as to airtightly separate them.

Each of the etching chambers 11 (11a, 11b, 1)
The wafer (substrate) 20 carried into 1c is subjected to an etching process under predetermined conditions. During this time, the load lock chamber (substrate receiving chamber) 5 is returned to the atmospheric pressure by the gas introducing device 4 with the isolation valves 12a and 12b closed, and the same as the first wafer from the opened isolation valve 12a. 2
The first wafer is loaded by the first transfer device 13,
It is evacuated again to a predetermined pressure by the exhaust device.
When the etching processing of the first wafer (substrate) 20 is completed, the isolation valve 12c is opened, and the processed wafer (substrate) 20 is carried out to the unload lock chamber (substrate unloading chamber) 6, and then the isolation valve is opened. 12c is closed and the isolation valve 12 is closed.
b is opened, the second wafer is carried in from the load lock chamber (substrate receiving chamber) 5, and after the isolation valve 12b is closed, the etching process is started.

The processed wafer (substrate) 20 carried out to the unload lock chamber (substrate unloading chamber) 6 returns to the atmospheric pressure in the unload lock chamber (substrate unloading chamber) 6, and then passes through the first isolation valve 12d. It is taken out to the atmosphere by the transport device 13 and returned to the original position in the cassette 1a that was initially stored.

By repeating the above operation, the processing of the unprocessed wafers stored in the cassette 1a is completed, and when the wafers are stored again in the original position, the cassette 1a can be collected.
The apparatus is replaced with a cassette containing another unprocessed wafer, but the apparatus continues to process the unprocessed wafers in the cassette 1b, and another unprocessed wafer is processed before all the wafers in the cassette 1b are completely processed. When a cassette containing wafers is supplied, the apparatus can always be operated continuously. At this time, since the cassette 1a and the cassette 1b are on the same horizontal plane, the operation of collecting the cassette 1a and the operation of supplying a cassette containing another unprocessed wafer are not affected by the access to the cassette 1b by the transfer device 13. Can be done without giving.

In the etching chamber 11, the reaction product adheres to and accumulates on the inner wall surface as the processing is repeated. Therefore, it is necessary to remove the adhered substance by plasma cleaning and restore the original state. In practice, the dummy wafers 30 stored in the cassette 1c are extracted by the first transfer device 13, and thereafter the processing is performed in exactly the same manner as in the case of the processing target wafer (substrate) 20. Can be returned to the original position in the cassette 1c, and the dummy wafers 30 are always stocked in the cassette 1c.

If all of the dummy wafers 30 in the cassette 1c have been used for plasma cleaning, or if the use of the dummy wafers 30 has failed several times, the dummy wafer 30
Are exchanged every cassette 1c.

Therefore, it is not necessary to treat the plasma cleaning as a special processing sequence, the plasma cleaning can be performed as a series of operations by incorporating the cleaning into a normal etching process, and the cleaning cycle can be arbitrarily set. is there. There is no need for a special mechanism for plasma cleaning from the hardware of the apparatus, and the dummy wafer 30 is mounted on one of the plurality of cassette tables (2c in this example).
It is only necessary to install a cassette (1c in this example) in which the wafer to be processed 20 is stored instead of the cassette in which the dummy wafer 30 is stored. It is needless to say that the installation enables more efficient production.

Further, since the dummy wafer once used for the plasma cleaning is returned to the original cassette in the atmosphere again, the used dummy wafer in the vacuum chamber and the normal processing are to be processed therefrom. Unprocessed wafers are not mixed, and there is no concern about product contamination.

[0022]

According to the present invention, it is possible to provide a transfer system for a vacuum processing apparatus which realizes high production efficiency and high product yield by eliminating product contamination due to generation of dust and residual gas.

[Brief description of the drawings]

FIG. 1 is a plan view of a dry etching apparatus according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate cassette, 2 ... Cassette stand, 5 ... Load lock chamber (substrate receiving chamber), 6 ... Unload lock chamber (substrate unloading chamber), 8 ... Sample table, 11 ... Etching chamber, 12 ... Isolation valve, 13 ... First transfer device, 16: transfer chamber, 20: wafer (substrate), 30: dummy wafer.

[Procedure amendment]

[Submission date] March 27, 2000 (2003.
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008]

The present invention SUMMARY OF] is placed a transfer chamber connected to a plurality of vacuum processing chamber for vacuum processing one by one the processing substrate, the Luke sets can plurality housed board in the air
And the cassette stand, cassette and one of the true of the atmosphere
A lock chamber for carrying substrates in and out of the empty processing chamber ;
Said substrate <br/> a method of transporting a substrate in a vacuum processing apparatus equipped with the atmosphere transfer device for transferring one by one, placed of the cassette table between the cassette and the lock chamber of the atmosphere
After processing the substrate in the first cassette in one of the vacuum processing chambers, the second cassette placed on the cassette table is processed.
The vacuum processing chamber with a dummy substrate in the preparative and dry cleaning, a vacuum processing chamber that the dry cleaning, hank
The method is characterized in that substrates in a third cassette placed on a cassette table are processed. According to the present invention, cleaning is
There is no need to treat it as a separate processing sequence.
Incorporating it as a series of operations by incorporating it into the
Can be set and the cleaning cycle can be set arbitrarily.
It is possible. Plus from the hardware of the device
There is no need for a special mechanism for cleaning.
Just install a cassette containing dummy substrates on the
Good for applications that do not require plasma cleaning
Is a processing target instead of a cassette containing dummy substrates.
By installing a cassette containing substrates,
Production can be performed efficiently. Also, once the plasma
The dummy substrate used for leaning is once again
In a vacuum chamber
Will receive the used dummy substrate and the formal processing from now on
The unprocessed substrate that is going to be mixed
No need to worry about contamination.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsunehiko Tsune 794 Kazato, Higashi-Toyoi, Kudamatsu City, Yamaguchi Prefecture Inside the Kasado Plant of Hitachi, Ltd. Inside the Kasado Plant of Hitachi, Ltd.

Claims (1)

[Claims] 1. A transfer chamber connected to a plurality of vacuum processing chambers for vacuum processing a substrate to be processed one by one and a plurality of cassettes capable of storing a plurality of substrates to be processed or processed substrates are placed in the atmosphere. A cassette table, a lock chamber for carrying in the substrate to be processed from the cassette in the atmosphere, and unloading the substrate to be processed into any one of the vacuum processing chambers via the transfer chamber; And another lock chamber for carrying the processed substrate through the transfer chamber and unloading the processed substrate to the cassette in the atmosphere, and the lock chamber in the atmosphere and any one of the lock chambers. A substrate processing method in a vacuum processing apparatus comprising: an atmospheric transfer device that transfers the substrate to be processed or the processed substrate one by one between the substrates. After the processing, the vacuum processing chamber is dry-cleaned, and the substrate in the cassette is processed in the dry-cleaned vacuum processing chamber.