JPH065535A - Heat treatment furnace - Google Patents

Abstract

(57) [Summary] [Object] To provide a heat treatment furnace capable of uniformly supplying a raw material gas injected into a reaction container to a sample such as a semiconductor wafer. [Structure] The gas injection unit 14 includes a gas injection unit 14a,
It is composed of a gas introduction pipe 14b. The gas injection part 14 a is formed in a substantially semi-cylindrical shape, and its outer surface is formed in the same shape as the inner surface of the reaction container 12. The gas injection part 14 a is brought into close contact with the inner surface of the reaction container 12. In the reaction container 12, the semiconductor wafers 2 are housed in a quartz boat 24 at regular intervals so that the surface of the semiconductor wafer 2 is horizontal. The raw material gas is injected into the reaction container 12 through a large number of injection holes 44 provided on the inner surface of the gas injection unit 14a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment furnace used when, for example, a semiconductor wafer is subjected to an oxidation treatment, a diffusion treatment and a treatment by a CVD method in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art FIG. 2 shows a schematic sectional view of a conventional vertical heat treatment furnace. In the figure, a large number of semiconductor wafers 52 are housed in a quartz boat 62 at regular intervals. The quartz boat 62 is placed inside the reaction container 64. The reaction container 64 has a cylindrical shape with an upper part having a hemispherical shape, and an opening is provided at the lower end thereof. A heater 66 is provided around the reaction container 64, and the heater 66 performs heating necessary for the reaction between the semiconductor wafer 52 and the raw material gas.

The manifold 68 is attached to the lower portion of the reaction vessel 64, and is provided with a gas discharge port 72 for discharging the raw material gas used in the reaction to the outside. Further, in the manifold 68, a gas introduction pipe 76 for supplying the raw material gas into the reaction container 64 is airtightly supported by an O-ring 74. The gas introduction pipe 76 is made of a single quartz pipe and has a vertical portion extending upward along the inner surface of the reaction vessel 64 and a horizontal portion. In the vertical portion of the gas introduction pipe 76, the source gas sent from the outside is horizontally jetted toward the semiconductor wafer 52 in the reaction container 64.
A large number of injection holes (not shown) are provided at regular intervals. The gas introduction pipe 76 is supported by a support ring 78 provided above the inner surface of the reaction container 64 so as to maintain a constant distance from the inner surface of the reaction container 64.

[0004]

By the way, the reaction vessel 6
In the inside of 4, the gas introduction pipe 76 is supported only by the support ring 78 provided on the upper portion of the inner surface of the reaction vessel 64. Therefore, the support ring 78 must be manufactured with a margin so that the gas introduction pipe 76 can be easily inserted and the quartz pipe is not damaged. That is, the gas introduction pipe 76 is not completely fixed and has a play. Therefore, the vertical portion of the gas introduction pipe 76 may be tilted to hinder the horizontal injection of the raw material gas.

If the raw material gas is not sprayed horizontally as described above, a flow of the raw material gas parallel to the surface of the semiconductor wafer cannot be obtained, and the sprayed raw material gas does not hit the semiconductor wafer uniformly. For this reason, in the conventional apparatus, there is a problem that the source gas is not uniformly supplied to a portion near the gas introduction pipe and a portion far from the gas introduction pipe even for the same wafer, and a predetermined processing result cannot be obtained on the semiconductor wafer. .

The present invention has been made in view of the above circumstances, and an object thereof is to provide a heat treatment furnace capable of uniformly supplying a raw material gas injected into a reaction container to a sample such as a semiconductor wafer. It is a thing.

[0007]

In order to achieve the above object, the present invention has a reaction vessel and a substantially semi-cylindrical shape, and a raw material gas is injected into the reaction vessel on a concave inner surface. A plurality of openings are formed, a convex outer surface is formed so as to be in close contact with the inner surface of the reaction container, and a gas injection means provided in the reaction container so that the outer surface is in close contact with the reaction container. And discharge means for discharging the source gas in the reaction container to the outside.

[0008]

According to the present invention, according to the above construction, the gas injection means is provided so that the outer surface of the gas injection means is in close contact with the inner surface of the reaction vessel. Therefore, the opening of the gas injection means always faces the predetermined direction. It can be held in a parallel state. As a result, the source gas can be jetted in parallel to the surface of the sample placed in the reaction vessel.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1A is a schematic cross-sectional view of a heat treatment furnace as an embodiment of the present invention as seen from above, and FIG. 1B is a schematic cross-sectional view of the heat treatment furnace as seen from the side.

The heat treatment furnace shown in FIG.
Gas injection means 14, manifold 16, furnace lid 18
The heat insulating cylinder 22, the quartz boat 24, and the heater 26 are provided. Here, a vertical heat treatment furnace in which the reaction vessel 12 and the heater 26 are vertically arranged is used.

The reaction container 12 has a cylindrical shape with an upper part having a hemispherical shape, and the lower end thereof is an open port. Reaction vessel 12
Are erected vertically on the manifold 16 with high accuracy. The gas injection unit 14 includes a gas injection unit 14a and a gas introduction pipe 14b. The gas injection part 14 a is formed in a substantially semi-cylindrical shape, and its outer surface is formed in the same shape as the inner surface of the reaction container 12. Further, a large number of injection holes 44 are formed in a lattice pattern at regular intervals on the inner surface of the gas injection unit 14a. The gas injection unit 14a is in close contact with the inner surface of the reaction container 12.

The manifold 16 is a mount attached to the lower surface of the reaction vessel 12. The manifold 16 has
A gas discharge port 32 for discharging the raw material gas used in the reaction to the outside is provided. Further, in the manifold 16, the gas introduction pipe 14 b is airtight by the O-ring 34.
It is supported.

The bottom of the manifold 16 is sealed by a furnace lid 18. A heat retaining tube 22 is placed on the furnace lid 18, and a quartz boat 24 containing the semiconductor wafer 2 is placed on the heat retaining tube 22. The semiconductor wafer 2 is kept at a constant interval so that its surface is horizontal and the quartz boat 24
Is stored in. The heat insulation cylinder 22 is rotatable.

The heater 26 is provided around the reaction container 12, and by this, the heating required for the reaction between the semiconductor wafer 2 and the raw material gas injected into the reaction container 12 is performed.

Next, the operation of the heat treatment furnace of this embodiment will be described. First, the furnace lid 18 removed from the bottom of the manifold 16 in order to house the semiconductor wafer 2 in the furnace.
A quartz boat 24 accommodating the heat retaining cylinder 22 and the semiconductor wafer 2 is placed on the above. In this state, the furnace lid 18 is lifted by a lifting device (not shown), the quartz boat 24 is inserted into the reaction vessel 12, and the furnace lid 18 is fixed to the manifold 16.

Next, in order to subject the semiconductor wafer 2 to a predetermined heat treatment, first, the heat retaining cylinder 22 is rotated and the heater 26 is operated. When the source gas is supplied from the gas introduction pipe 14b, the source gas is injected into the reaction vessel 12 through the injection holes 44 formed in the inner surface of the gas injection unit 14a. The raw material gas jetted from the jetting holes 44 is horizontally and uniformly supplied to the surface of the semiconductor wafer 2, and the semiconductor wafer 2 and the raw material gas react with each other in a high temperature atmosphere, so that the semiconductor wafer 2 is subjected to a predetermined treatment. It

In the heat treatment furnace of this embodiment, the outer surface of the gas injection part is formed to have the same shape as the inner surface of the reaction vessel, and the gas injection part is closely attached to the inner surface of the reaction container. Since it can be fixed to the inner surface of the reaction container, the injection hole of the gas injection unit can be maintained in a horizontal state. In particular, in this embodiment, since the gas injection part is formed in a semi-cylindrical shape, the gas injection part does not move in the left-right direction in FIG. 1 (b), and the deviation of the gas injection part can be prevented. Therefore, since the raw material gas can be sprayed horizontally onto the surface of the semiconductor wafer, the raw material gas can be uniformly supplied to a large number of semiconductor wafers accommodated in the quartz boat inside the reaction container. As a result, the entire semiconductor wafer can be uniformly processed, and the throughput of the semiconductor manufacturing process can be improved.

The present invention is not limited to the above embodiment, but various modifications can be made within the scope of the gist thereof. For example, in the above embodiment, the case where a large number of injection holes are formed on the inner surface of the gas injection portion in a grid pattern at regular intervals has been described, but the present invention is not limited to this, and the injection holes are at least It is sufficient to form one row in the vertical direction.

[0019]

As described above, according to the present invention, the outer surface of the gas injection means and the inner surface of the reaction vessel are formed in the same shape, and the gas injection means is brought into close contact with the inner surface of the reaction vessel. Since the gas injection means can be fixed to the inner surface of the reaction container, the opening of the gas injection means can be held in a state of being always parallel to a predetermined direction. Thus, it is possible to provide a heat treatment furnace that can be processed in the same manner and can improve the throughput.

[Brief description of drawings]

FIG. 1A is a schematic cross-sectional view of a heat treatment furnace according to an embodiment of the present invention as seen from above, and FIG. 1B is a schematic cross-sectional view of the heat treatment furnace as seen from the side.

FIG. 2 is a schematic sectional view of a conventional heat treatment furnace.

[Explanation of symbols]

 2 semiconductor wafer 12 reaction container 14 gas injection means 14a gas injection part 14b gas introduction pipe 16 manifold 18 furnace lid 22 heat retaining tube 24 quartz boat 26 heater 32 gas exhaust port 34 O-ring 44 injection hole

Claims (1)

[Claims] 1. A reaction vessel and a substantially semi-cylindrical shape, a concave inner surface having a large number of openings for injecting a raw material gas into the reaction vessel, and a convex outer surface having the reaction surface. A gas injection unit that is formed so as to be in close contact with the inner surface of the container and is provided in the reaction container so that the outer surface is in close contact with the reaction container, and a discharge unit that discharges the raw material gas in the reaction container to the outside. And a heat treatment furnace.