JPH08316153A - Vapor growth apparatus - Google Patents

Abstract

PURPOSE: To achieve the uniformity of the rate of gas fed furthermore and to decrease the variation in thickness and quality of a grown film to a large extent by decentering many gas blowing ports of a diffusion plate, expanding the gas distribution, and providing wing-shaped projections in the direction to the outer surfaces of the gas blowing ports. CONSTITUTION: In a disk-shaped diffusion plate 9, many gas blowing ports are provided in the decentering pattern. Wing-shaped projections 10 are provided on the side of the outer surface direction. The plate is rotated by a rotary motor 11. The gas introduced through a gas introducing port 4 is uniformly diffused by the rotating diffusion plate 9 and sent into a shower head 8 through the gas blowing ports. The gas blown from the shower head 8 is uniformly supplied on a substrate 3 on a susceptor 2. A semiconductor film is grown by heat, plasma or the like. The projections become larger toward the outer- surface direction. Thus, sucking of the gas in the vicinity of the center of the diffusion plate 9 is weak. The sucking of the gas becomes intense toward the outer surface. In this way, the rate of gas fed through the gas blowing port can be made uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus,
In particular, it relates to a vapor phase growth apparatus for growing a film on a semiconductor substrate.

[0002]

2. Description of the Related Art A conventional vapor phase growth apparatus, as shown in FIG. 5 (A), supplies gas from a gas inlet 4 and supplies gas through a shower head 8 (see "Prior Art Example 1"). ")). Then, in FIG. 5 (A), in order to make the gas supply uniform under constant conditions of pressure and gas flow rate, a vapor phase growth apparatus having a configuration in which the location and hole diameter of the gas ejection port of the shower head 8 are appropriately changed. There is also ("Conventional example 2").

Further, as shown in FIG. 5 (B), there is also a structure in which a diffusion plate 9 is provided upstream of the shower head 8 for uniform gas supply (referred to as "conventional example 3"). .

Further, for example, in Japanese Patent Laid-Open No. 4-43634, for the purpose of providing an apparatus capable of forming a formed film having a uniform composition and film thickness on the wafer surface, as shown in FIG. A configuration has been proposed in which a gas supply tool having a plurality of gas inlets 4 is rotated about each rotary shaft 12 to supply gas (referred to as "conventional example 4").

[0005]

However, the above conventional vapor phase growth apparatus has the following problems.

In the conventional example 1 (see FIG. 5A) in which gas is supplied through the shower head 8 of the vapor phase growth apparatus, the gas is supplied from the gas ejection port just below the gas introduction port 4 and in the vicinity thereof. The amount is large, and the grown film thickness is not uniform (see the distribution of “conventional example” in FIG. 4 showing the gas flow distribution diagram).

Further, in the vapor phase growth apparatus of the conventional example 2 having a structure in which the location of the gas outlet of the shower head 8 and the hole diameter are changed, the shower head 8 needs to be replaced when the growth conditions are changed. . In the conventional example 2, the grown film thickness is not uniform, though it is not as thick as the grown film thickness of the conventional example 1 (see the distribution of "conventional example" in FIG. 4).

In the conventional example 3 (see FIG. 5B) in which the diffusion plate 9 is provided on the upstream side of the shower head 8,
Prior art example 1 in which gas is supplied through the shower head 8
Similarly, the amount of gas supplied in the vicinity of the gas inlet 4 is large, and the grown film thickness is not uniform (see the distribution of “conventional example” in FIG. 4).

Further, in the conventional example 4 (see FIG. 6), the gas is uniformly supplied on the rotation circumference of the gas inlet 4, but the gas is supplied except for the rotation locus of the rotary shaft 12 and the gas inlet 4. The supply amount is reduced, resulting in non-uniform supply. Further, the gas flow is disturbed by the rotation of the gas inlet 4, and the grown film thickness is not uniform (see the distribution of “conventional example” in FIG. 4).

Therefore, the present invention solves the above problems and makes the gas supply amount uniform in a vapor phase growth apparatus for supplying a gas from a gas ejection plate having a plurality of holes to grow a film on a semiconductor substrate. It is an object of the present invention to provide an apparatus for reducing variations in the thickness and quality of grown films.

[0011]

In order to achieve the above object, the present invention provides a vapor phase growth in which a gas is blown from a gas jet plate having a plurality of holes (shower head) to grow a film on a semiconductor substrate. In the apparatus, there is provided a vapor phase growth apparatus which is provided on the upstream side of the gas ejection plate and is provided with a diffusion plate which is rotatable about a gas ejection direction and has a plurality of gas ejection ports eccentrically provided. provide.

In the present invention, preferably, the diffusion plate has a disc shape, and is provided with a blade-shaped projection in the outer peripheral direction of the gas ejection port, and the projection becomes larger toward the outer periphery. It is characterized by

The present invention is preferably characterized in that the diffusing plate is constructed so that the rotation speed can be freely set.

[0014]

According to the present invention, a large number of gas outlets of the diffusion plate are eccentrically arranged so that the gas distribution is widened, and the blade-like projections are provided in the outer peripheral direction of the gas outlets to feed the gas. In addition to achieving a more uniform amount of gas, the thickness and quality of the grown film can be greatly reduced, and the growth conditions can be changed by controlling the rotational speed of the diffusion plate, and the gas supply that responds to changes in gas viscosity, etc. Enables stabilization.

[0015]

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

FIG. 1 is a diagram for explaining the overall structure of a vapor phase growth apparatus according to an embodiment of the present invention. FIG. 1 shows a vapor phase growth apparatus equipped with a diffusion plate which constitutes a feature of the present invention.

Referring to FIG. 1, the gas flows from the introduction pipe to the mass flow controller 6 via a plurality of stop valves 7. Next, the gases whose flow rate is controlled by the mass flow controller 6 merge and reach the gas inlet 4 via the stop valve 7 '.

The diffusion plate 9 has a gas ejection port, is provided with a blade-shaped projection 10 on the outer peripheral side of the gas ejection port, and is rotatably supported by a predetermined rotation support member such as a bearing. The rotation motor 11 rotates about the gas ejection direction.

The gas introduced from the gas introduction port 4 is uniformly diffused by the rotating diffusion plate 9, and is sent to the shower head 8 from the gas ejection port of the diffusion plate 9.

The gas ejected from the shower head 8 is
It is uniformly supplied to the substrate 3 on the susceptor 2, and a semiconductor film is grown by heat or plasma.

Next, the diffusion plate 9 for uniformly diffusing gas will be described.

FIG. 2 is an enlarged view for explaining the structure of the vapor phase growth apparatus having the diffusion plate 9 according to the embodiment of the present invention shown in FIG. 1, and FIG. 3 shows the diffusion plate 9 itself. 2 is a plan view and a partially enlarged view of the wing-shaped projection 10. FIG.

Referring to FIG. 3, the disc-shaped diffusion plate 9 includes
A large number of gas ejection ports 13 are eccentrically provided.

In the present embodiment, since the large number of gas ejection ports 13 are eccentric, the rotation trajectory area of the gas ejection ports is larger than that of the configuration in which the gas ejection ports are concentrically arranged. That is, the distribution of the gas fed from the gas ejection port to the shower head 8 becomes wider.

Further, the diffusion plate 9 is provided with a blade-shaped projection 10 on the outer peripheral side of the gas ejection port. Feather-shaped protrusion 10
Has a function of sucking gas like a ventilation fan by the rotation of the diffusion plate 9, and sends the gas to the shower head 8 from the gas ejection port.

Referring to FIGS. 2 and 3, the protrusion 10 is provided so as to be larger toward the outer peripheral direction. With such a configuration, the gas suction is weak near the center of the diffusion plate 9, and the gas suction becomes stronger toward the outer periphery, and as a result, the amount of gas fed from the gas ejection port is made uniform ( See the distribution of "this embodiment" in FIG.

Referring to FIG. 2, the diffusion plate 9 is rotatably supported by a predetermined rotation supporting member such as a bearing 14 and is held by the predetermined rotation supporting member, and at the same time, a rotary motor (electric motor) 11 and a gear. The rotational drive is controlled by (speed reducer) 15 and the like, and the number of rotations can be set to a desired value.

When the rotating speed of the diffusion plate 9 is low, the suction of gas by the blade-shaped projections 10 becomes weak. It is suitable for low-viscosity introduced gases, ie gases that are easy to diffuse.

On the other hand, when the rotation speed is high, a blade-shaped protrusion
The gas suction of 10 becomes strong. This is suitable for a gas having a high viscosity.

As described above, in the present embodiment, by providing the blade-shaped projections in the outer peripheral direction of the gas ejection port of the diffusion plate 9, it is possible to achieve uniform gas feeding amount and
By variably controlling the number of revolutions of the diffusion plate 9, there is an effect that the gas supply is stabilized in response to changes in gas viscosity and the like.

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment,
As a matter of course, it includes various aspects according to the principle of the present invention.

[0032]

As described above, according to the present invention,
By eccentrically arranging a large number of gas outlets, the gas distribution can be widened, and by providing blade-shaped projections in the outer peripheral direction of the gas outlets, the amount of gas fed can be made even more uniform. This has the effect of making it possible to change the growth conditions by controlling the rotation speed of the diffusion plate and to stabilize the gas supply in response to changes in gas viscosity and the like. That is, according to the vapor phase growth apparatus of the present invention, it is possible to supply a uniform gas, and it is possible to achieve more uniform growth of the semiconductor film than the conventional example.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a vapor phase growth apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of an exemplary embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of an exemplary embodiment of the present invention.

FIG. 4 is a diagram showing a gas flow rate distribution of an example of the present invention and each conventional example.

FIG. 5 is a diagram showing a configuration of a conventional vapor phase growth apparatus.

FIG. 6 is a diagram showing a configuration of a conventional vapor phase growth apparatus.

[Explanation of symbols]

 1 Chamber 2 Susceptor 3 Substrate 4 Gas Inlet 5 Exhaust 6 Mass Flow Controller 7 Stop Valve 8 Shower Head 9 Diffuser 10 Protrusion (Wing) 11 Rotating Motor 12 Rotating Shaft 13 Gas Injecting Port

Claims (3)

[Claims] 1. A vapor phase growth apparatus for supplying a gas from a gas spouting plate having a plurality of holes to grow a film on a semiconductor substrate, wherein the gas spouting plate is rotated upstream from the gas spouting plate. 1. A vapor phase growth apparatus comprising a diffusion plate which is freely movable and is provided with a plurality of gas ejection ports in an eccentric manner. 2. The diffusion plate has a disk shape, is provided with a blade-shaped protrusion in the outer peripheral direction of the gas ejection port, and the protrusion is increased toward the outer periphery. The vapor phase growth apparatus according to claim 1. 3. The vapor phase growth apparatus according to claim 1, wherein the diffusion plate is configured so that the rotation speed is freely set.