JPH09115838A - Film forming system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate stand by time in forming thin film with a simple structure and at low cost. SOLUTION: When the film forming of approximately 180 seconds of a wafer W, that is held by a wafer supporting part 3b, is started, another wafer W held by the wafer holding part 3a, of which film forming is just finished, is mounted on an elevator 7, the elevator 7 is lower to a predetermined position and the semiconductor wafer W is cooled for 30 seconds preliminarily. Then the treated semiconductor wafer W is stored and a new semiconductor wafer W, that is before the treatment, is mounted on the elevator 7, the elevator 7 is raised to a position at a predetermined distance from the wafer holding part 3a and the preheating of the wafer W of a approximately 30 seconds is started. By performing the upper stated operation continuously, the treatment of the semiconductor wafers W is proceeded continuously without stand by time.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a film forming apparatus,
In particular, the present invention relates to a technique effective when applied to the reduction of the waiting time in the atmospheric pressure CVD apparatus.

[0002]

2. Description of the Related Art In manufacturing a semiconductor integrated circuit device, as an example of a film forming apparatus for forming various thin films such as conductive films or resistance films on a semiconductor wafer, a semiconductor wafer is placed in a reaction chamber under atmospheric pressure. Atmospheric pressure CVD (Chemi) for introducing a reaction gas to chemically deposit a desired thin film
Cal Vapor Deposition) devices are widely known.

According to a study made by the present inventor, this atmospheric pressure CVD apparatus is a semiconductor in which the surface of a semiconductor wafer is held downward in a reaction chamber by a wafer holding section containing a heater for heating the semiconductor wafer. A desired thin film is deposited by bringing a gas head for blowing a reaction gas close to a wafer and blowing the reaction gas for a certain period of time.

As an example in which this type of film forming apparatus is described in detail, the Industrial Research Institute Co., Ltd., published on November 25, 1994, Masashi Oshima (ed.) “VLSI Manufacturing / Testing Equipment Guidebook <1995. Annual edition> ”P44-P47
This document describes the current state and trends of CVD technology such as atmospheric pressure CVD equipment.

[0005]

However, the present inventor has found that the film forming technique in the above CVD apparatus has the following problems.

That is, in order to hold the semiconductor wafer by the wafer supporting portion heated by the heater or to remove the semiconductor wafer from the wafer supporting portion, the wafer supporting portion should be supported in order to prevent warping or cracking of the semiconductor wafer due to a rapid temperature change. A waiting time is required to keep the space between the wafer and the semiconductor wafer at a predetermined interval and heat them for a certain period of time.

Therefore, during the waiting time, the film forming process cannot be performed, which causes a problem that the processing capacity of the CVD apparatus is lowered.

There is also an atmospheric pressure CVD apparatus provided with a plurality of gas heads in order to improve the processing capacity, but in this case, the cost of the apparatus itself increases and the structure becomes complicated.

An object of the present invention is to provide a film forming apparatus which has a simple structure and which can eliminate the waiting time at the time of film formation at a low cost.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0011]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

That is, in the film forming apparatus of the present invention, the object to be processed is supplied to one reaction gas supply means for supplying a reaction gas, which is a raw material for film formation, to a reaction chamber which is a film forming chamber for forming a thin film. Of the two or more processed product holding means, the processed product holding means for holding the processed product to be film-formed is provided. When facing the gas supply means, at least one other processing object holding means has a structure facing the mounting means for mounting the processing object.

Further, in the film forming apparatus of the present invention, the processing object holding mechanism is provided with a rotatable shaft provided in a reaction chamber for forming a thin film on an object to be processed, and an outer peripheral portion from a center of the rotating shaft. It is composed of two or more processing object holding means provided so as to extend to the.

Further, in the film forming apparatus of the present invention, the pressure of the reaction chamber provided with the processed material holding mechanism is atmospheric pressure.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a CV according to an embodiment of the present invention.
It is a principal part explanatory drawing of a D apparatus.

In the present embodiment, the CVD apparatus (film forming apparatus) 1 is provided with a reaction chamber 2 for forming a thin film at a predetermined position, which is made of, for example, aluminum, and the upper portion of the reaction chamber 2 is formed. A wafer holding mechanism (processed object holding mechanism) 3 that processes and transfers a semiconductor wafer (processed object) W on which a thin film is formed is provided in the.

Further, in this embodiment, this CVD
The apparatus is a normal pressure CVD in which the reaction chamber 2 is at atmospheric pressure.
Equipment.

Further, in the wafer holding mechanism 3, wafer holding portions (processed object holding means) 3a, 3b for holding two semiconductor wafers W are provided on the left and right sides extending from the center of the rotation shaft 3c to the peripheral portion. The rotating shaft 3c is connected to a driving unit such as a motor and is rotatable.

Further, a heater 4 for heating the semiconductor wafer W and a vacuum pipe 5 for sucking and holding the semiconductor wafer W by a vacuum chuck are provided inside the wafer holding portions 3a, 3b.

Further, in order to prevent the heater 4 from directly contacting the semiconductor wafer W, the contact surfaces of the wafer holding portions 3a and 3b which contact the semiconductor wafer W are made of, for example, SiC (silicon carbide). A susceptor 6 is provided.

An elevator part (mounting means) 7 for mounting the semiconductor wafer W is provided in the lower part of the reaction chamber 2, and the elevator part 7 is also connected to a driving part such as a motor to move vertically. It is movable.

Further, the elevator part 7 is provided with a support part 7a made of, for example, quartz, which comes into contact with the back surface of the semiconductor wafer W at a predetermined position. When the semiconductor wafer W is placed, this support part 7a is provided. Only the portion 7a comes into contact with the back surface of the semiconductor wafer W.

Further, below the reaction chamber 2, there is provided a dispersion head (gas supply means) 8 for supplying a reaction gas for forming a thin film on the semiconductor wafer W, and inside this dispersion head 8. For example, a predetermined number of plate-shaped dispersion plates 8a made of aluminum are continuously provided in the width direction of the dispersion head 8.

The dispersion head 8 has a T
A gas pipe 8b for introducing a raw material such as EOS (organic oxysilane) and a carrier gas is provided.

The elevator section 7 and the dispersion head 8 are respectively provided with the wafer holding sections 3a and 3a.
It is provided at a position facing 3b.

The above-mentioned drive unit, supply of the reaction gas introduced into the dispersion head 8, control of the vacuum chuck mechanism and thin film formation, and the like are responsible for all control of the CVD apparatus 1 provided in the CVD apparatus 1. It is controlled by a unit (not shown).

Next, the operation of the present embodiment will be described.

First, a semiconductor wafer W to be processed is transferred from a wafer cassette (not shown), which is provided in the vicinity of the reaction chamber 2 and stores unprocessed semiconductor wafers W, by a transfer system (not shown) to an elevator section 7. Place on top.

Then, the heater 4 is used for 300 to 40 in advance.
The elevator unit 7 is moved up to a predetermined position by the drive unit on the wafer support 3a heated to about 0 ° C., and preheating is performed at that position for a predetermined time, for example, about 30 seconds,
After that, the elevator section 7 is raised to move the wafer holding section 3a.
By vacuuming the vacuum piping of the semiconductor wafer W
Are vacuum-adsorbed.

Next, the wafer holding mechanism 3 is rotated by 180 degrees about the rotary shaft 3c by the driving unit to position the wafer holding unit 3a above the dispersion head 8,
The reaction gas is introduced from the gas pipe 8b, and the processing of the semiconductor wafer W is started.

Semiconductor wafer W in the wafer holder 3a
When the processing is started, the transfer system transfers the semiconductor wafer W to be processed from the wafer cassette, and the elevator unit 7
The semiconductor wafer W is placed on top.

Here, since the wafer holding mechanism 3 is rotated by 180 degrees, the wafer supporting portion 3b, which is preheated to about 300 to 400 ° C. by the heater 4, is positioned above the elevator portion 7. Will be.

Then, the elevator section 7 is raised to a predetermined position by the drive section, preheated for about 30 seconds, for example, and then the elevator section 7 is raised to evacuate the vacuum pipe 5 of the wafer holding section 3b. By doing so, the semiconductor wafer W is vacuum-sucked.

Next, when the processing of the semiconductor wafer W held by the wafer holding portion 3a is completed, the introduction of the reaction gas from the gas pipe 8b is stopped, and the wafer holding mechanism 3 is again driven by the driving portion to 180 degrees. The rotation is done.

The wafer holding unit 3a of the wafer holding mechanism 3 rotated by 180 degrees by the driving unit is mounted on the elevator unit 7 which is moved to a position just below the wafer holding unit 3a by the driving unit, and the vacuum pipe 5 is attached. After the vacuum evacuation is stopped and the processed semiconductor wafer W is detached and placed, the elevator unit 7 is lowered to a predetermined position to precool the semiconductor wafer for a predetermined time, for example, about 30 seconds.

At this time, at the same time, the introduction of the reaction gas from the gas pipe 8b is started, and the semiconductor wafer W held by the wafer holding portion 3b located above the dispersion head 8 is held for a predetermined time, for example, 180 seconds. Do some processing.

Next, during the film forming process of the semiconductor wafer W held by the wafer holder 3b, when the semiconductor wafer W held by the wafer holder 3a is precooled for about 30 seconds as described above, The elevator unit 7 descends to a predetermined position and stores the processed semiconductor wafer W in the wafer cassette, which is provided in the vicinity of the reaction chamber 2 by the transfer system.

Thereafter, similarly, the transfer system transfers the semiconductor wafer W to be processed from the wafer cassette, which is provided in the vicinity of the reaction chamber 2 and stores the unprocessed semiconductor wafer W, and places it on the elevator section 7. Then, preheating for about 30 seconds is started.

By continuously performing the above operation, the semiconductor wafer W is continuously processed without waiting time.

As a result, in the present embodiment, by providing the wafer holding portions 3a and 3b, it is possible to perform residual heat and cooling of the semiconductor wafer W during processing of the semiconductor wafer W, thus improving throughput. You can

Further, it is not necessary to additionally install the dispersion head 8 and the gas pipe 8b, and the processing capacity can be increased at a low cost with a simple device configuration.

Although the invention made by the inventor has been specifically described based on the embodiments of the present invention, the present invention is not limited to the above embodiments, and various modifications may be made without departing from the gist of the invention. Needless to say, it can be changed.

For example, in the above-described embodiment, two wafer supporting portions were provided in the reaction chamber for one dispersion head, but by setting the number of these wafer supporting portions to three or more. Also, the throughput can be improved satisfactorily.

[0045]

Advantageous effects obtained by typical ones of the inventions disclosed by the present application will be briefly described as follows.
It is as follows.

(1) According to the present invention, the waiting time of the object to be processed is greatly shortened by providing the processed material holding mechanism composed of two or more processed material holding means for one gas supply means. can do.

(2) Further, according to the present invention, since it is not necessary to add a gas supply means or the like, the processing capacity can be increased by a simple and low-cost device configuration.

(3) Further, in the present invention, the throughput in semiconductor manufacturing can be improved by the above (1) and (2).

[Brief description of the drawings]

FIG. 1 is an explanatory view of essential parts of a CVD apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CVD apparatus (film-forming apparatus) 2 Reaction chamber 3 Wafer holding mechanism (processed object holding mechanism) 3a Wafer holding part (processed object holding means) 3b Wafer holding part (processed object holding means) 3c Rotating shaft 4 Heater 5 Vacuum piping 6 Susceptor 7 Elevator part (placement means) 7a Support part 8 Dispersion head (gas supply means) 8a Dispersion plate 8b Gas pipe W Semiconductor wafer (object to be processed)

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H01L 21/31 H01L 21/31 B 21/68 21/68 P

Claims (3)

[Claims] 1. A gas supply unit for supplying a reaction gas, which is a raw material for film formation, to a reaction chamber, which is a film formation chamber for forming a thin film, for holding and heating an object to be processed. A processed product holding mechanism including the above processed product holding means is provided, and the processed product holding means holding the processed product on which the film is to be formed is opposed to the gas supply means among the two or more processed product holding means. Then, at least any one of the other processing object holding means has a structure facing the mounting means for mounting the processing object. 2. The film forming apparatus according to claim 1, wherein the processed object holding mechanism includes a rotatable shaft provided in a reaction chamber for forming a thin film on an object to be processed, and a center of the rotational shaft. A film forming apparatus comprising: two or more processing object holding means provided extending to an outer peripheral portion. 3. The film forming apparatus according to claim 2, wherein the pressure of the reaction chamber provided with the processed material holding mechanism is atmospheric pressure.