JPH11274268A - Vacuum treating device and vacuum treatment method of substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide vacuum treatment and a vacuum treatment method for achieving high production efficiency. SOLUTION: A vacuum treating device is provided with a cassette rest 2 that horizontally maintains a substrate in a cassette 1 to be placed, a first carrying device 13 that is arranged so that it can access a plurality of cassettes 1 on the cassette rest 2 and a substrate loading room 5 or a substrate unloading room 6, a carrier room 16 that is constituted so that a plurality of vacuum treatment rooms 11 can be connected to a periphery with the substrate loading and substrate unloading rooms 5 and 6, and a second carrying device that is provided in the carrier room 16 and is arranged so that it can access the substrate loading and substrate unloading rooms 5 and 6 and a plurality of vacuum treatment rooms 11.

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 previously housed in a vacuum preparatory chamber is loaded into the processing chamber when performing plasma cleaning of the processing chamber. 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]

In order to achieve the above object, the present invention provides a first loader operating in an air atmosphere, a second loader operating in a vacuum atmosphere, the first loader and the second loader. Wherein the first loader is located outside the lock chamber and includes a cassette table on which a plurality of cassettes storing substrates are placed. A substantially horizontal surface for mounting the cassette, and a cassette mounting surface disposed in front of the lock chamber, wherein the cassette mounting surface is provided in the cassette on which the cassette is mounted. The substrate is configured to be supplied to and recovered from the lock chamber while keeping the processing surface horizontal.

Another feature of the present invention is that in a substrate vacuum processing method for processing substrates one by one using a plurality of vacuum processing chambers, a substrate in an air atmosphere is transferred through a first lock chamber. Loading the substrate into the vacuum processing chamber, processing the substrate in the vacuum processing chamber, and transporting the substrate processed in the vacuum processing chamber to the atmosphere via a second lock chamber. The vacuum processing chamber is maintained at a vacuum during the loading and unloading of the substrate.

According to the present invention, a cassette accommodating unprocessed substrates is placed on the cassette table. At this time, since the cassette table is horizontal, the supply operation of the cassette can be simplified, and it is easy to respond to automation of the production line.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a diagram showing an application of a vacuum processing apparatus according to the present invention to an apparatus for performing a dry etching process on a semiconductor wafer.

The apparatus is provided with a plurality (usually 25) 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 containing unprocessed wafers are supplied from a stocker (not shown) to the apparatus by a robot or an operator, and placed 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 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 the embodiment, the dummy wafer 30 stored in the cassette 1c is 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 dummy wafers 30 have failed due to several uses, the dummy wafers 30 will not be used.
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 is to be subjected to regular processing. Unprocessed wafers are not mixed, and there is no concern about product contamination.

[0025]

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.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Atsushi Ito 794, Higashi-Toyoi, Kazamatsu-shi, Yamaguchi Prefecture Inside the Kasado Plant of Hitachi, Ltd.

Claims (2)

[Claims] 1. A vacuum processing apparatus comprising: a first loader operating in an air atmosphere; a second loader operating in a vacuum atmosphere; and a lock chamber connecting the first loader and the second loader. The one loader includes a cassette table which is located outside the lock chamber and on which a plurality of cassettes accommodating the substrates are mounted, and the cassette table is provided from a substantially horizontal surface for mounting the cassette. And a cassette mounting surface disposed in front of the lock chamber. The cassette mounting surface is configured such that the substrate in the cassette mounted thereon is in contact with the lock chamber while maintaining the processing surface horizontal. A vacuum processing apparatus characterized in that the vacuum processing apparatus is configured to be supplied and recovered between them. 2. A vacuum processing method for a substrate in which a plurality of vacuum processing chambers are used to process substrates one by one, wherein a substrate in an air atmosphere is carried into the vacuum processing chamber via a first lock chamber. Processing the substrate in the vacuum processing chamber; and transporting the substrate processed in the vacuum processing chamber to the atmosphere through a second lock chamber. Wherein the vacuum processing chamber is maintained at a vacuum during unloading.