JPH0225031A - Ecr type plasma cvd system - Google Patents

Abstract

PURPOSE:To improve the production efficiency of insulating film of wafers by a method wherein wafers are mounted in radial shape on a rotatable wafer stage so that all the wafers may be passed by the position on the axis of a plasma leading-out window by rotating the stage. CONSTITUTION:Wafers 9 are set on the mounting positions of a wafer stage 80. A reaction chamber 20 is once sealed and then exhausted to lead-in material gas of plasma. When the plasma is produced, reaction product is deposited on a wafer 9 positioned below a plasma leading-out window 7. When the reaction product film attains to the specified thickness, a motor 201 is supplied with power to turn the stage 80 for positioning the wafer 9 in the part below the window 7 so that the reaction product may be deposited on the wafer 8. Similar procedures, are repeated for all the wafers 9.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an insulating film forming apparatus for use in semiconductor integrated circuits.
This invention relates to an ECR type plasma CVD apparatus.

[Conventional technology]

The basic configuration of a conventional ECR type plasma CVD apparatus is shown in FIG.

The conventional device 1 has a reaction chamber 2 and a plasma chamber 3.

The plasma chamber 3 is connected to a microwave waveguide 5 via a microwave-transparent partition plate 4, and an electromagnet 6 is provided around it, which generates ECR (Electron Cyclotron Resonance) along with microwaves within the plasma chamber 3. It is possible to establish conditions and form a divergent magnetic field for drawing out plasma within the reaction chamber 2. This plasma chamber 3 is connected to the reaction chamber 2 via a plasma extraction window 7, and the plasma is transmitted to a wafer 9 placed on a wafer stage 8 coaxially provided with the plasma extraction window 7 in the reaction chamber 2. It is accelerated and guided by a diverging magnetic field.

According to this device, an N2 gas introduction pipe 10 is inserted into a plasma chamber 3 in which ECR conditions are set using microwaves and a magnetic field.
N, NH, 0°A, or a mixture thereof is sent through the reactor 2, and the plasma-formed gas is guided by the divergent magnetic field and sent to the reaction chamber 2. On the other hand, in the reaction chamber 2, there is a wafer 9 placed on a wafer stage 8, and an S
A raw material gas for forming an insulating film such as iH, SIH, 5t3H8 is supplied to the reaction chamber 2 via a raw material gas introduction pipe 102,
This is excited and activated by the plasma to cause a reaction, and predetermined reaction products are deposited on the wafer 9. ECR
Inorganic material film (insulating film) formed by plasma CVD method
Although 5iaN4 films are currently being formed, 510
2. A silicon nitride oxide film can also be formed.

[Problem to be solved by the invention]

However, when plasma is generated using an ECR type plasma source, it is generally not possible to generate uniform plasma over a wide area. Therefore, even when performing this on the wafer stage of the conventional apparatus, the area corresponding to one wafer of about 3 to 4 inches was the maximum area in which plasma could be generated.

Therefore, when forming an insulating film on a wafer using the conventional apparatus, the insulating film could only be formed by placing the wafers one by one on a wafer stage, and the production rate was low. This is because the time required to generate an insulating film on one wafer includes not only the time for plasma reactants to be deposited on the wafer, but also the time for placing and setting the wafer on the wafer stage. This is because, after all, it takes a considerable amount of time to form an insulating film on one wafer, including the time required for evacuation after installation.

Therefore, the present invention makes it possible to place multiple wafers on the wafer stage at once, thereby reducing the time required for placing and setting each wafer, and increasing the production efficiency of the insulating film on the wafer. The purpose is to

[Means to solve the problem]

The apparatus according to the present invention is an ECR type plasma CVD apparatus that deposits a reaction product for forming an insulating film on a wafer set coaxially with a plasma extraction window. A central part is supported by a rotating shaft, and a plurality of wafers can be placed radially and at a distance from the central part, and all of the wafers are coaxial with the plasma extraction window. The wafer stage is characterized by comprising a wafer stage that is rotatable about a rotation axis so that the wafer can pass through the position of the wafer.

[Effect]

The apparatus according to the present invention is capable of placing a plurality of wafers on a rotatable wafer stage supported by a rotating shaft at a distance radial and temporal from the center of the wafer stage. Therefore, in the apparatus of the present invention, when the wafer stage rotates around the rotation axis, all of the wafers pass through a position coaxial with the plasma extraction window,
Furthermore, since the reaction product can be deposited on the wafer at that time, it becomes possible to form the insulating film on a plurality of wafers at once.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to FIGS. 1 and 2 of the accompanying drawings. In addition, in the description of the drawings, the same elements are given the same reference numerals, and redundant description will be omitted.

FIG. 1 is a sectional view of an apparatus according to an embodiment of the present invention.

As shown in the figure, the apparatus 10 of the present invention is different from the conventional apparatus i1 shown in FIG. Rotating shaft 200 is connected to motor 201 and supports the center position of wafer stage 80 . For this reason, the wafer stage 80 is
Due to the driving force of 01, the rotating shaft 200 rotates stepwise in a fixed direction around the rotating shaft 200.

Furthermore, although the plasma extraction window 7 is located approximately in the center of the upper surface of the reaction chamber 2, the rotating shaft 200 is not located at the center of the reaction chamber 2 because it is located non-coaxially with the plasma extraction window 7. Therefore, in order to rotate the wafer stage 80 around the rotation axis 200, the reaction chamber 2 protrudes to the side away from the rotation axis 200 by a sufficient amount for the wafer stage 80 to rotate.

Further, the rotation axis 200 and the center of the wafer stage 80 are located non-coaxially with the plasma extraction window 7, and the mounting position of the wafer 9, which is arranged radially and equidistantly from the center of the wafer stage 80, is located at the plasma extraction window. It is located on the same axis as 7. Therefore, as the wafer stage 80 rotates, the placement position of the wafer 9 always passes coaxially with the plasma extraction window 7. Therefore, when the wafer 9 passes through a position coaxial with the plasma extraction window 7 , reaction products extracted from the plasma extraction window 7 are deposited on the wafer 9 .

Next, the operation of the apparatus according to the above embodiment will be explained.

First, before depositing reaction products, the wafer 9 is set at the mounting position of the wafer stage 80. Next, the reaction chamber 20
After sealing, the chamber is evacuated, plasma conditions are established as described above, and source gas is introduced. Then, reaction products are deposited on the wafer 9 located below the plasma extraction window 7.

When the film formed by the reaction product reaches a predetermined thickness, or when deposition has been performed for a predetermined time, the motor 201 is energized to rotate the wafer stage 80 in steps. As a result, the next wafer 9 is positioned below the plasma extraction window 7, and the reaction products are deposited again.

After the same process is performed on all wafers 9 on the wafer stage 80, the plasma condition is canceled and the supply of source gas is stopped. Then, the vacuum in the reaction chamber 20 is released, and the wafer 9 is taken out. In this way, even when depositing reaction products on multiple wafers 9, setting the wafers 9, evacuation, establishing plasma conditions, etc. can be done all at once.
It will be possible to do it in one go.

FIG. 2 is a perspective view showing a specific example of the wafer stage.

As shown in FIG. 1A, a rotating shaft 200 (shown in FIG. 1) supports the center of the wafer stage 80, and a rotating shaft holder 81
is connected to the center of the wafer stage 80 by. The wafer stage 80 is characterized in that a plurality of wafers are placed radially and equidistantly around the rotating shaft holder 81, and therefore has a size that allows a plurality of wafers 9 to be placed thereon. Furthermore, it takes the form of a disk. As a result, each wafer 9 placed near the outer edge of the wafer stage 80 at an equal distance from the rotating shaft holder 81 is always positioned coaxially with the plasma extraction window 7 when the wafer stage 80 rotates around the rotating shaft. pass.

Further, as shown in FIG. 2(b), a wafer stage 80
may consist of a plurality of wafer mounting plates 82 on which wafers 9 are placed, a plurality of support rods 83 each having the same length, and a rotation shaft center plate 84 having a rotation shaft holder 81. One of the wafer placement plates 82 only needs to be able to place one of the wafers 9, and only needs to be approximately the same size or larger than the wafer 9. Furthermore, the wafer mounting plate 82 is connected to the rotation center plate 84 by support rods 83 that protrude radially from the rotation shaft center plate 84 having the rotation holder 81 and the rotation shaft. Therefore, it is possible to rotate in conjunction with the rotation of the rotation axis,
All of the wafer mounting plates 82 pass through a position coaxial with the plasma extraction window 7 due to their rotation, and at this time, generated reactants are deposited on the wafers 9. In addition, in the wafer stage 80 of FIG. 2(b), the reaction products blown out over a wider area than the wafer 9 when pulled out from the plasma extraction window 7 are removed from the space created around the wafer mounting plate 84 and the support rod 83. can be dropped. As a result, when excess reaction products that are not deposited on the wafer 9 hit the wafer stage 80,
This can prevent it from flying around.

〔Effect of the invention〕

The apparatus according to the present invention includes, on a rotatable wafer stage,
A plurality of wafers can be placed radially and at substantially the same distance from the center of the wafer stage supported by the rotation shaft. Therefore, when the wafer stage rotates around the rotation axis, all of the multiple wafers can pass through a position coaxial with the plasma extraction window. This makes it possible to deposit and form an insulating film. Thereby, when forming an insulating film, the time required for mounting and setting each wafer can be shortened, and the production efficiency of the insulating film on the wafer can be increased.

Furthermore, since the device configuration can be changed relatively easily, the manufacturing cost of the device itself is almost the same as that of conventional devices.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the device of the present invention, and FIG.
This figure is a perspective view showing a wafer stage according to the present invention, and FIG. 3 is a sectional view of a conventional device. 2... Reaction chamber, 3... Plasma chamber, 4... Microwave transparent partition plate, 5... Micro waveguide, 6...
- Electromagnet, 7... Plasma extraction window, 8... Wafer stage, 80... Wafer stage, 81... Stage holder, 82... Wafer mounting plate, 83... Support rod, 84... ... center of wafer mounting plate, 9... wafer,
100...N2 gas introduction pipe, 102...Material gas introduction pipe, 200...Rotating shaft, 201...Motor patent applicant Sumitomo Electric Industries Co., Ltd. Representative Patent Attorney Yoshiki Hase Microwave No. 1 Figure 2 Perspective view of the stage

Claims (1)

[Claims] 1. In an ECR type plasma CVD apparatus that deposits a reaction product for forming an insulating film on a wafer set coaxially with a plasma extraction window, a rotating shaft supported by the rotating shaft, a plurality of wafers can be placed radially and at substantially the same distance from the center, and all of the wafers are connected to the plasma drawer. An ECR type plasma CVD apparatus comprising a wafer stage rotatable about the rotation axis so that the wafer stage can pass through a position coaxial with the window. 2. The wafer stage includes a plurality of wafer mounting plates that are radially and at approximately the same distance from the center supported by the rotating shaft and that can place only one wafer, and the center 2. The ECR type plasma CVD apparatus according to claim 1, further comprising support rods projecting from said wafer mounting plate in each direction from said wafer mounting plate in order to support said wafer mounting plate.