JPH065533A - Heat treatment furnace - Google Patents

Abstract

PURPOSE:To provide a heat treatment furnace uniformly feeding semiconductor wafers with material gas jetted into a reaction chamber. CONSTITUTION:An inner reaction chamber 14 is placed within an outer reaction chamber 12. A large number of holes 14a are vertically formed at a specified interval in the left and right side walls of the inner reaction chamber 14; the positions of the individual holes 14a on the left side correspond to those on the right side. Semiconductor wafers are placed at a specific interval in a quartz boat 26 in the inner reaction chamber 14 such that their surfaces are horizontal. Material gas is introduced into a space between the outer reaction chamber 12 and the inner reaction chamber 14, and jetted into the inner reaction chamber 14 through the holes 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. 3 is 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, since the gas introducing pipe 76 is made of a single quartz pipe, it is difficult to process the vertical portion and the horizontal portion so as to form an angle of 90 degrees, and to some extent. The error of is inevitable. Therefore,
The vertical portion of the gas introduction pipe 76 is not completely parallel to the inner surface of the reaction container 64, and as a result, the flow of the raw material gas parallel to the semiconductor wafer 52 cannot be obtained. Further, inside the reaction container 64, 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 container 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, if the horizontal portion of the gas introduction pipe 76 that is airtightly supported by the O-ring 74 shifts in the left-right direction in the figure, the vertical portion also moves and tilts at the same time, which may 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. Therefore, in the conventional apparatus, there is a problem in that even if the same wafer is used, the source gas is not uniformly supplied to the portion near the gas introduction pipe and the portion far from the gas introduction pipe, 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]

A heat treatment furnace according to the present invention for achieving the above object comprises a first reaction vessel and a large number of openings formed in the side surface of the first reaction vessel. A second reaction container is provided, a sample is placed in the second reaction container, and a source gas is introduced into the second reaction container through the opening to react with the sample and discharged to the outside through the opening. It is characterized by doing.

Further, it is desirable that the space sandwiched between the first reaction vessel and the second reaction vessel be divided into an inflow side space and an outflow side space for the raw material gas.

[0009]

According to the present invention, the second reaction vessel is arranged in the first reaction vessel and a large number of openings are provided on the side surface of the second reaction vessel according to the above-mentioned constitution. To be discharged to the outside. In general,
The bottom of the reaction vessel has a high processing accuracy, and the central axis of the opening and the bottom surface of the second reaction vessel can be formed in parallel with each other with high accuracy. Therefore, the raw material gas injected from the opening into the second reaction container can flow exactly parallel to the surface of the sample on the flat plate, and the raw material gas is uniformly supplied to the surface of the sample.

Further, by dividing the space sandwiched between the first reaction container and the second reaction container into a space for the inflow side and a space for the outflow side of the raw material gas, the raw material gas is always arranged in the second reaction container. Since the sample can be supplied to the prepared sample, the source gas can be efficiently used.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of a heat treatment furnace which is a first embodiment of the present invention.

The heat treatment furnace shown in FIG.
, The internal reaction vessel 14, the manifold 18, and the furnace lid 2
2, a heat insulating cylinder 24, a quartz boat 26, and a heater 28. Incidentally, here, the reaction vessels 12, 1
4 and a heater 28 having a vertical structure in which a heater 28 is vertically arranged.

The outer reaction vessel 12 and the inner reaction vessel 14 are
Both have a cylindrical shape with an upper part having a hemispherical shape, and the lower end thereof is an opening. The inner reaction vessel 14 is the outer reaction vessel 1.
It is placed inside 2. Further, as shown in FIG. 1, a large number of holes 14a are vertically formed at predetermined intervals on the right side surface and the left side surface of the inner reaction container 14. The holes 14a formed on the right side surface and the left side surface are formed at positions facing each other in the horizontal direction.

The manifold 18 is a mount attached to the lower surfaces of the outer reaction vessel 12 and the inner reaction vessel 14. In the manifold 18, the raw material gas is fed to the external reaction vessel 1
A gas inlet 32 to be introduced into the inside of the chamber 2 and a gas outlet 34 for discharging the raw material gas used in the reaction to the outside are provided. Further, the space sandwiched between the outer reaction container 12 and the inner reaction container 14 constitutes a passage for the raw material gas introduced from the gas introduction port 32.

The bottom of the manifold 18 is sealed by a furnace lid 22. A heat insulation tube 24 is placed on the furnace lid 22, and a quartz boat 26 containing the semiconductor wafer 2 is placed on the heat insulation tube 24. The semiconductor wafer 2 is kept at a constant interval so that its surface is horizontal and the quartz boat 26
Is stored in. The heat insulation cylinder 24 is configured to be rotatable.

The heater 28 is provided around the outer reaction container 12, and by this, the heating necessary for the reaction between the semiconductor wafer 2 and the raw material gas injected into the inner reaction container 14 through the hole 14a is performed.

Next, the operation of the heat treatment furnace of the first embodiment will be described. First, the furnace lid 2 removed from the bottom of the manifold 18 in order to store the semiconductor wafer 2 in the furnace.
A quartz boat 26 accommodating the heat retaining cylinder 24 and the semiconductor wafer 2 is placed on the upper part 2. In this state, the furnace lid 22 is lifted by a lifting device (not shown), the quartz boat 26 is inserted into the inner reaction vessel 14, and the furnace lid 22 is moved to the manifold 1.
Fix at 8.

Next, in order to subject the semiconductor wafer 2 to a predetermined heat treatment, first, the heat retaining cylinder 24 is rotated and the heater 28 is operated. When the source gas is supplied from the gas inlet 32,
The raw material gas passes through the space sandwiched between the outer reaction container 12 and the inner reaction container 14, and part of the gas enters the inner reaction container 14 through the hole 14a formed in the side surface of the inner reaction container 14. The raw material gas sprayed from the holes 14a is horizontally and uniformly supplied to the surface of the semiconductor wafer 2, and the semiconductor wafer 2 and the raw material gas react in a high temperature atmosphere, so that the semiconductor wafer 2 is subjected to a predetermined process.

In the heat treatment furnace of the first embodiment, the inner reaction vessel is further arranged in the outer reaction vessel, and a large number of holes are provided on the side surfaces of the inner reaction vessel which face each other. It is supplied to the semiconductor wafer through the hole formed on the side surface and discharged to the outside through the hole formed on the other side surface. Generally, since the bottom of the reaction vessel has a high level of horizontal processing accuracy, the bottom surface of the internal reaction vessel and the surface of the semiconductor wafer can be parallelized with high accuracy. It is possible to accurately flow the raw material gas injected into the inside in the horizontal direction from the hole formed on the side surface of the internal reaction container. Therefore, the source gas can be uniformly supplied to the surface of the semiconductor wafer,
The entire semiconductor wafer can be uniformly processed, and the throughput of the semiconductor manufacturing process can be improved.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a schematic sectional view of a heat treatment furnace which is a second embodiment of the present invention. In the heat treatment furnace of the second embodiment, those having the same functions as those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The heat treatment furnace of the second embodiment differs from that of the first embodiment in that the outer reaction vessel 120 and the inner reaction vessel 1 are different.
Partition 16 for partitioning the space sandwiched between 40 and 40
That is the point. Further, the outer reaction container 120, the inner reaction container 140 and the partition 16 are integrally formed including the gas introduction port 32 and the gas discharge port 34.

In the heat treatment furnace of the second embodiment, the space sandwiched between the outer reaction vessel and the inner reaction vessel is divided into two parts, so that the raw material gas introduced from the gas introduction port is always in the inner reaction vessel. The semiconductor wafer is supplied through the holes. For this reason, the raw material gas does not enter the inner reaction vessel and is not directly discharged to the outside, so that the raw material gas can be efficiently used. In addition, other actions
The effect is similar to that of the heat treatment furnace of the first embodiment.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention. For example, in each of the above-described embodiments, a case has been described in which holes are formed in a row in the up-down direction on the side surfaces of the inner reaction vessel which face each other, but the present invention is not limited to this, and the holes on each side are Two or more rows may be formed in the vertical direction. Further, the opening is not limited to the hole, and may have a slit shape, for example.

[0024]

As described above, according to the present invention, by disposing the second reaction container in the first reaction container and providing a large number of openings on the side surface of the second reaction container, The raw material gas injected into the second reaction container can be made to flow exactly parallel to the surface of the sample, and therefore the entire surface of the semiconductor wafer can be uniformly processed in the semiconductor manufacturing process, thus improving the throughput. It is possible to provide a heat treatment furnace capable of performing the heat treatment.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a heat treatment furnace which is a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a heat treatment furnace which is a second embodiment of the present invention.

FIG. 3 is a schematic sectional view of a conventional heat treatment furnace.

[Explanation of symbols]

 2 Semiconductor wafer 12,120 External reaction vessel 14,140 Inner reaction vessel 14a Hole 16 Partition 18 Manifold 22 Furnace lid 24 Insulating cylinder 26 Quartz boat 28 Heater 32 Gas inlet 34 Gas outlet

Claims (2)

[Claims] 1. A first reaction vessel, and a second reaction vessel arranged in the first reaction vessel and having a large number of openings on its side surface. A sample is placed in the second reaction vessel. A heat treatment furnace, wherein a raw material gas is introduced into the second reaction container through the opening to react with the sample and is discharged to the outside through the opening. 2. The heat treatment furnace according to claim 1, wherein a space sandwiched between the first reaction container and the second reaction container is partitioned into an inflow side space and an outflow side space of the raw material gas.