JPS63257232A - Treatment apparatus - Google Patents

Abstract

PURPOSE:To make it possible to move treatment gas, which is blown through a treatment gas head, on a material to be treated uniformly, by arranging a carrier gas head and an exhausting means on both sides of the treatment gas stream. CONSTITUTION:When a wafer 1 is mounted on a susceptor 3 with a handler, the susceptor 3 is rotated with a driving device 6 through a rotary shaft 7. The wafer 1 is heated with a heater 5 through the susceptor 3. Meanwhile, nitrogen gas is uniformly blown out of a carrier gas head 20 into a treatment chamber 2. The gas in the treatment chamber 2 is uniformly exhausted as a whole through a side-part exhausting hood 22. In this way, the layered stream of the nitrogen gas, which is discharged through the carrier head 20 and sucked into an exhaust port 23, is uniformly formed on the entire surface of the wafer 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a processing technology, particularly a processing technology for subjecting a workpiece to a desired treatment using a reactive processing gas.
The present invention relates to a technique that is effective for forming an oxide film on a wafer in the manufacturing process of semiconductor devices.

[Conventional technology]

In the manufacturing process of semiconductor devices, when forming an oxide film on a wafer, an atmospheric pressure CVD apparatus is sometimes used. The wafer is continuously transferred in the lateral direction in the vicinity of the outlet, and the CVD film is deposited on the wafer. There are some that are configured like this.

An example of the oxide film formation technology described is "Electronic Materials November 1983 Special Edition" published by Kogyo Research Association Co., Ltd.
Published on November 15, 1981, pages P75 to P81 are available.

As described in many documents including the above-mentioned document, in vapor phase growth processing technology including atmospheric pressure CVD technology, film thickness and film quality (impurity concentration, crystallinity) can be made uniform and high. Accurate formation, improved mass productivity, and processing stability for large-diameter wafers are required. In response to this demand, particularly for the purpose of reducing manufacturing costs of semiconductor devices, wafers of large diameter are being used as objects to be processed. Furthermore, from the viewpoint of improving the characteristics of products, even higher integration is required, and therefore the patterns of products tend to become even finer.

[Problem that the invention seeks to solve]

However, in such atmospheric pressure CVD equipment, the following points are not taken into account, so it is difficult to maintain uniformity of film quality and film pressure, step coverage is poor, and the process of generating CVD films is , reaction products are generated,
This becomes foreign matter by adhering to the wafer surface.
There is a problem that the yield of product characteristics decreases, and furthermore, when an oxide film containing phosphorus is generated, the concentration distribution of the phosphorus molecular weight interposed in the oxide film becomes uneven, increasing the variation in resistivity on the wafer surface. The inventor of the present invention has revealed that there is a problem in that the yield is reduced.

An object of the present invention is to provide a processing technique that improves film quality, uniformity of film thickness, and step coverage, and provides good film characteristics with less foreign matter.

A further object of the present invention is to provide a processing technique that, in the production of an oxide film containing phosphorus, makes the concentration of phosphorus contained in the film uniform and improves the concentration distribution.

Another object of the present invention is to provide a compact single-wafer processing snowmaking system capable of processing large-diameter wafers.

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

[Means for solving problems]

An overview of typical inventions disclosed in this application is as follows.

In other words, a reactive processing gas is uniformly discharged from a gas head equipped with a plurality of elongated gas outlets, and this processing gas is mixed with a carrier gas discharged from a carrier gas head disposed on one side, and a carrier gas disposed on the other side. The exhaust means is used to uniformly diffuse the water in the water direction and to flow it along the surface of the object on the susceptor.

[Effect]

According to the above-mentioned means, the processing gas blown out from the processing gas head is uniformly transferred onto the wafer by the carrier gas discharged from the horizontal direction, so that the concentration distribution of the processing gas is uniform, and the film formed on the wafer is The thickness and uniformity of phosphorus concentration distribution are improved.

Furthermore, by rotating the susceptor, uniformity is promoted, and even more precise film formation becomes possible.

In the conventional method, in order to obtain uniformity of film thickness, it was essential to horizontally move the head from side to side or to move the susceptor horizontally. However, according to the above means, the desired accuracy can be obtained by simply rotating the head or the susceptor while the head remains stationary, so there is no need for a means for horizontally moving the head or the susceptor, so there is no need for such a complicated mechanism. The configuration of the device is simplified and can be manufactured at low cost. Furthermore, the simplification of the mechanism reduces the amount of dust generated from the element parts that make up the mechanism, ie, the sliding parts, etc., resulting in an even cleaner device.

Furthermore, since the mechanism for horizontally moving the head or susceptor of the conventional device described above is no longer required, the vibrations generated by this movement are reduced, and this imaging reduces the probability that reaction products will be detached from around the susceptor. Therefore, the probability that this separated product will adhere to the object to be processed is also reduced, and product defects due to adhesion of foreign matter can be reduced.

〔Example〕

FIG. 1 is a longitudinal cross-sectional view showing a single-wafer atmospheric pressure CVD gastomer according to an embodiment of the present invention, and FIG. 2 is a plan cross-sectional view taken along the line n--■ in FIG.

In this example, a single-wafer atmospheric pressure CVD as a processing device
The device is equipped with a processing chamber 2 for performing CD processing on a wafer 1 as an object to be processed, and a susceptor 3 for holding the wafer is disposed at the lower part of the processing chamber 2. The susceptor 3 is disposed at the upper end opening of the frame 4, and a heater 5 is housed inside the frame 4 so as to heat the wafer 1 on the susceptor 3. A drive device 6 consisting of a servo motor or the like is installed below the frame 4, and the susceptor 3 is configured to be rotationally driven by the drive device 6 via a rotating shaft 7. The frame body 4 and the drive device 6 are configured to be able to move up and down with respect to the processing chamber 2 (not shown).
, the wafer 1 is transferred onto the susceptor 3 by a handler (not shown) between a loader and an unloader outside the processing chamber 2 while the wafer 1 is positioned on the lower side.

In the upper part of the processing chamber 2, there is a roughly cubic processing gas chamber 1.
1 is suspended. A plurality of elongated slit-shaped outlets 12 are provided on the lower surface of the processing gas head 11 so that the processing gas can be blown out toward the susceptor 3, and each outlet 12 is arranged parallel to each other with both ends aligned. It is set up. Inside the head 11, a gas passage 3 is provided for each outlet 12.
The gas passages 12 are formed in a hollow shape in which the blow-off ports 12 are continuous in the vertical direction, and the gas passages 13 are cut off from communication with each other. Also, head 1
Two systems of gas supply passages 14a and 14b are formed inside the gas supply unit 1, and adjacent gas passages 13a and 13b are alternately connected to both supply passages 14a and 14b, respectively.

The processing gas head 11, which is installed to blow out processing gas downward, is arranged so as to be offset by a predetermined distance with respect to the center line of the susceptor 3.

A gas head for discharging carrier gas is installed beside the side on which the processing gas head 11 is shifted, and this gas head 20 is configured to uniformly discharge nitrogen gas as a carrier gas throughout. has been done. That is, like the processing gas head, this carrier gas head 20 is also provided with a large number of ejection ports 21 opened in the shape of elongated slits.

Processing gas head 11 opposite to carrier gas head 20
A side exhaust hood 22 as an exhaust means is disposed on one side of the susceptor 3, and an exhaust port 23 is opened in the exhaust hood 22 so as to surround the susceptor 3 on three sides except for the carrier gas head 20. has been done. An exhaust duct 24 is connected to the exhaust hood 23, and an exhaust volume 2 (not shown) consisting of a vacuum pump or the like is connected to the exhaust duct 24. A plurality of dampers 25 are installed in the exhaust hood 22 and are distributed on the upstream side and the downstream side so as to control the amount of exhaust gas and the suction direction at the exhaust port 23.

Next, the action will be explained.

When the wafer 1 is placed on the susceptor 3 by the handler, the susceptor 3 is rotated by the drive value device 6 via the rotating shaft 7, and the wafer 1 is heated by the heater 5 via the susceptor 3. At this time, since the susceptor 3 is being rotated, the wafer 1 is heated uniformly as a whole, and the temperature distribution of the wafer 1 becomes uniform.

On the other hand, nitrogen gas is supplied to the processing chamber 2 from the carrier gas head 20.
At the same time, the entire processing chamber 2 is uniformly exhausted by the side exhaust hood 22. As a result, a laminar flow of nitrogen gas discharged from the carrier gas head 20 and sucked into the exhaust port 23 is uniformly generated over the entire surface of the wafer 1.

A laminar flow is generated on the wafer 1, and the wafer 1 reaches a predetermined temperature (
For example, when the temperature reaches 350℃ to 550℃,
Processing gases such as phosphine (PH3) + monosilane (SiHt), oxygen (01), nitrogen (N2), etc. are uniformly blown out from the processing gas head 11. For example, an oxide film containing phosphorus is formed on the wafer 1. When generating gas, predetermined gases such as phosphine and oxygen are supplied to the gas supply passages 15a and 15b of the gas head 11, respectively, and the gas passages 14a and 1
The air is blown out from the slit-shaped air outlet 12 through the air outlet 4b.

The blown processing gas is flown in the direction of the exhaust port 23 by the carrier gas flow uniformly generated on the wafer 1, so that it comes into contact with the wafer 1 one after another. As a result, a CVD film is generated on the wafer 1 in combination with heating.

At this time, since the processing gas head 11 is shifted in the upstream direction of the carrier gas with respect to the center of the wafer 1, the distribution of the degree of film formation (rate) on the wafer 1 becomes uniform overall. That is, the amount of contact with the wafer 1 of the processing gas flowing in the direction of the exhaust port tends to be larger on the downstream side of the wafer 1. On the other hand, since the processing gas comes into contact with the upstream side earlier, the processing gas that has been partially consumed on the upstream side flows to the downstream side. Therefore, from these relationships, by shifting the processing gas head 11 by a predetermined distance 9 degrees to the upstream side of the carrier gas with respect to the center of the wafer 1, the distribution of the degree of film formation can be made uniform throughout the entire region from upstream to downstream.

Furthermore, since the wafer 1 is rotated, the film formation distribution is reliably made uniform, and since the wafer 1 is oriented equally in all directions with respect to the gas flow, step coverage is also improved.

Furthermore, when phosphine is used as the process gas, CvDl! is uniformly supplied onto the wafer 1 by the carrier gas. :! The concentration distribution of the predistorted phosphorus contained therein becomes uniform.

Thereafter, the wafer 1 that has undergone the desired film-forming process is lowered from above the susceptor 3 by the handler, and the next wafer 1 is supplied. Thereafter, by repeating the above operations, the CVD processing power (single wafer type) is performed on the wafer 1.

According to the embodiment described above, the following effects can be obtained.

(1) The carrier gas discharged from the gas head placed on one side of the processing gas head allows the processing gas blown out from the processing gas head to be uniformly transferred onto the wafer, resulting in uniform film formation. can do.

(2) Due to (1) above, there is no need to horizontally move either the processing gas head or the susceptor, which simplifies the mechanism, reduces the overall size of the device, and eliminates the need for a large amount of space for mounting. and the equipment cost is also low.

(3) According to (2) above, there is no mechanical horizontal movement mechanism;
Since the generation of foreign matter caused by this transfer can be avoided, adhesion of foreign matter can be suppressed, and an even better film can be obtained.

(4) By configuring the processing gas to be moved horizontally over the wafer surface by the carrier gas and the susceptor rotating, the uniformity of the produced film can be further improved, and the processing gas can be used effectively. gas consumption can be reduced.

(5) By rotating the wafer, processing gas is uniformly supplied from the circumferential direction of the wafer.
The film formation distribution can be made uniform, and step coverage can be increased.

(6) When producing an oxide film containing phosphorus, the concentration distribution of phosphorus prestrain during film formation can be made uniform;
Variations in resistivity on the wafer surface can be suppressed, and a decrease in yield can be prevented.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nor.

For example, the carrier gas is not limited to nitrogen gas, but may also be a mixed gas with a processing gas, other inert gas, or the like.

The side exhaust hood is not limited to being configured to exhaust air from three directions of the processing gas head, but may be configured to exhaust air only from one direction facing the carrier head.

In addition, the side exhaust hood is not limited to an integral structure;
It may be configured to separate in the direction.

In the above explanation, the invention made by the present inventor was mainly applied to a single-wafer atmospheric pressure CVD apparatus, which is the background field of application, but the invention is not limited thereto ( The present invention can be applied to normal pressure equipment, other oxide film forming equipment, diffusion equipment, etc. The present invention can be applied to at least general processing equipment in which a workpiece is brought into contact with a processing gas.

(Effects of the Invention) The effects obtained by typical inventions disclosed in this application are as follows. 6. Carrier gas heads and exhaust means are arranged on both sides of the processing gas head. By setting up the processing gas head, the processing gas blown out from the processing gas head can be uniformly transferred onto the workpiece by the carrier gas discharged from the gas head arranged on one side of the processing gas head. processing can be carried out.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing a single-wafer atmospheric pressure CVD apparatus according to an embodiment of the present invention, and FIG. 2 is a plan cross-sectional view taken along the line ■-■ in FIG. l...Wafer (workpiece), 2...processing chamber, 3...
・Susceptor, 4... Frame, 5... Heater, 6...
Drive device, 7...Rotating shaft, 11...Processing gas head, 12...Blower outlet, 13a, 13b-...Gas passage,
14a, 14b...Gas supply path, 20...Carrier gas head, 2I...Discharge port, 22...Side exhaust hood (exhaust means), 23...Exhaust port, 24...Exhaust duct.

Claims (1)

[Claims] 1. A processing chamber, a susceptor provided to hold an object to be processed in the processing chamber, a gas head disposed to face the susceptor and blowing out a processing gas, and a gas head for blowing out processing gas. It is characterized by comprising a carrier gas head disposed on one side of the head and discharging carrier gas toward the other side, and an exhaust means disposed on the other side of the processing gas head for discharging the gas. processing equipment. 2. The processing apparatus according to claim 1, wherein the susceptor is shifted toward the exhaust means side with respect to the processing gas head. 3. The processing apparatus according to claim 1, wherein the susceptor is configured to rotate. 4. The processing device according to claim 1, wherein the carrier gas head is provided with a discharge port formed in the shape of a plurality of elongated slits so as to uniformly discharge the gas as a whole. . 5. The processing apparatus according to claim 1, wherein the exhaust means is configured to be able to adjust the suction direction and the exhaust amount. 6. Claim 1, characterized in that the processing gas head is configured to blow out multiple types of gases.
Processing equipment described in Section 1.