JPH03255621A - Heat treatment furnace - Google Patents

Abstract

PURPOSE:To cool down the elements to be processed so efficiently within a short time without deteriorating the quality thereof by a method wherein the title heat treatment furnace is provided with a cover part comprising a partly extended tube wall of a furnace core tube in addition to the heating part thereof, a basket cover of a quartz-made basket loaded with said elements, a cooling gas leading-in port and a driving part having the straight forward advancing and rotating functions. CONSTITUTION:Semiconductor wafers 4 are heat-treated at the temperature of processing gas in a furnace core tube 2 raised at the processing temperature of the semiconductor wafers 4. After the heat treatment, a quartz-made basket 3 loaded with the semiconductor wafers 4 is rotated by the driving part 3c of the basket 3 while the basket cover 3e is arranged on the opposite side of the cover part 2a of the furnace core tube 2. Later, with the processing temperature of the heat treatment furnace kept at a specific temperature, the semiconductor wafers 4 are encircled by the cover part 2a of the furnace core tube 2 and the basket cover 3e of the basket while leading-in an inert gas from a cooling gas leading-in port 3d, the basket 3 is taken out of the heating part of the furnace core tube 2 by advancing the driving part 3c straight forward to cool down the semiconductor wafers 4 by the cooling gas. Through these procedures, the semiconductor wafers 4 can be cooled down within a short time without oxidizing the wafers 4.

Description

[Detailed Description of the Invention] [Summary] Regarding a heat treatment furnace that can improve the processing method for processed objects, such as semiconductor wafers, it is possible to improve the processing method for processed objects, such as semiconductor wafers, without changing the processing temperature of the heat treatment furnace. The purpose of this heat treatment furnace is to provide a heat treatment furnace that can efficiently cool the material to be processed in a short period of time without degrading the quality of the material to be processed. hand,
In addition to the heating part of the furnace core tube, a cover part is provided by extending a part of the tube wall, and a cover part is provided which carries the object to be processed and surrounds the object to be processed, and is provided with a cover part extending straight from the cooling gas inlet. and a drive unit having a rotation function.

[Industrial application field]

The present invention relates to a heat treatment furnace that can improve the processing method for processed objects, such as semiconductor wafers.

It is necessary to cool down the heat-treated workpiece in the furnace core tube efficiently in a short time and without degrading the quality of the workpiece.

Under the above-mentioned circumstances, there is a need for a heat treatment furnace that can efficiently cool a workpiece in a short period of time without degrading the quality of the workpiece.

[Conventional technology]

The case of a conventional vertical heat treatment furnace will be explained in detail with reference to FIG.

A vertical heat treatment furnace used in a conventional diffusion process or CVD process is heated by a heater 11, as shown in FIG. This is a furnace into which a quartz basket 13 loaded with an object, for example, a semiconductor wafer 4, is inserted and the semiconductor wafer 4 is heat-treated.

This quartz basket 13 is attached to the furnace core tube 12 as shown in the figure.
A semiconductor wafer 4 is mounted on a base 13a having an outer diameter approximately equal to the outer diameter of the semiconductor wafer 4.
This is a quartz basket for handling semiconductor wafers 4, which has three wafer holding parts 13b with grooves formed at equal intervals into which wafers are inserted.

When using such a heat treatment furnace, first, the flow rate of the processing gas introduced from the processing gas inlet 12b is set by a mass flow controller (not shown), and the furnace is heated to a temperature lower than the processing temperature of the semiconductor wafer 4 by the heater 11. The temperature of the processing gas within the core tube 12 is increased.

In this state, as shown in Figure 4 (a.
-13 is raised using the drive part 13c and inserted into the furnace core tube 12. Thereafter, the temperature of the processing gas in the furnace core tube 12 is raised to the processing temperature of the semiconductor wafer 4 to perform heat treatment.

If the semiconductor wafer 4 that has undergone heat treatment is taken out while still being heated to the processing temperature, it will be oxidized by oxygen in the air, so the temperature of the processing gas in the furnace core tube 12 should be adjusted to the same temperature as when it was inserted. After similarly lowering the temperature to lower than the processing temperature, the quartz basket 13 is taken out and the semiconductor wafer 4 is taken out, thereby completing the heat treatment process.

[Problem to be solved by the invention]

In the conventional heat treatment furnace described above, in order to prevent the semiconductor wafer from being oxidized when taking out the semiconductor wafer after heat treatment, it is necessary to lower the temperature of the furnace to a temperature that can prevent oxidation. Since the temperature of the furnace must be raised each time the heat treatment is performed, there are problems in that the processing capacity of the heat treatment furnace is significantly reduced and the treatment temperature becomes unstable.

In view of the above-mentioned circumstances, the present invention makes it possible to efficiently cool the processed material after heat treatment in a short time without changing the processing temperature of the heat treatment furnace, and without degrading the quality of the processed material. The purpose is to provide a heat treatment furnace.

[Means to solve the problem]

The heat treatment furnace of the present invention is a heat treatment furnace for heat-treating a material to be treated in a furnace core tube, and is provided with a cover part extending a part of the tube wall in addition to the heating part of the furnace core tube, and The bottom of the tank is equipped with a quartz basket on which the workpiece is loaded, a basket cover surrounding the workpiece, a cooling gas inlet, and a drive unit having linear and rotational functions.

[Effect]

That is, in the present invention, a cover section that is an extension of a part of the tube wall of the furnace core tube is provided outside the heating section of the furnace core tube, and a quartz basket in which the object to be processed is mounted is provided with a basket cover that surrounds the object to be processed. , is equipped with a cooling gas inlet and a drive unit with linear and rotational functions, so after heat-treating the object, the drive unit is used to heat the quartz while keeping the processing temperature of the heat treatment furnace constant. The basket is removed from the furnace core tube, the workpiece is surrounded by the cover of the furnace core tube and the basket cover of the quartz basket, and non-oxidizing gas is introduced from the cooling gas inlet to cool the workpiece. It becomes possible to efficiently cool the processed material in a short time without oxidizing it.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A vertical heat treatment furnace according to an embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 3.

FIG. 1 is a diagram showing a schematic structure of a heat treatment furnace according to an embodiment of the present invention. As shown in the figure, this is a furnace in which heat treatment is performed by inserting a workpiece into a furnace core tube 2 which is heated by a heater 1 and has a processing gas inlet 2b provided at the top.

The furnace core tube 2 of this embodiment is partially different in structure from the conventional furnace core tube 12, and as shown in the figure, a substantially semicircular portion of the furnace core tube 2 has a long section at the bottom other than the heating section. A cover portion 2a corresponding to the heating portion of the furnace core tube 2 is provided in an extended manner.

FIG. 2 is a diagram showing a schematic structure of a quartz basket according to an embodiment of the present invention. As shown in the figure, this quartz basket 3 has a base 3a having a cooling gas inlet 3d which is approximately equal to the outer diameter of the furnace core tube 2, and a wafer holding portion 3b having grooves formed at equal intervals into which semiconductor wafers 4 are inserted. This is a quartz basket 3 for handling semiconductor wafers 4, in which three quartz baskets 3 are planted, and a substantially semicircular basket cover 3e is provided on the opposite side of a portion provided with a cooling gas inlet 3d.

When using such a heat treatment furnace, first, the flow rate of the processing gas introduced from the processing gas inlet 2b is set by a mass flow controller (not shown), and the temperature of the processing gas in the furnace core tube 2 is adjusted by the heater 1 to the temperature of the processing gas introduced from the processing gas inlet 2b. The temperature is raised to a temperature lower than the treatment temperature in step 4.

In this state, as shown in FIG. 3(a), the quartz basket 3
is raised by the drive part 3c and inserted into the furnace core tube 2.

Thereafter, the temperature of the processing gas in the furnace core tube 2 is raised to the processing temperature of the semiconductor wafer 4 to perform heat treatment.

After the heat treatment is completed, the quartz basket 3 carrying the semiconductor wafer 4 is rotated by the drive section 3c of the quartz basket 3, and the basket cover 3e is placed on the opposite side of the cover section 2a of the furnace core tube 2.

After that, one semiconductor wafer 4 is surrounded by the cover part 2a of the furnace core tube 2 and the basket cover 3e of the quartz basket 3 while keeping the processing temperature of the heat treatment furnace constant, and while introducing an inert gas from the cooling gas inlet 3d. , Figure 3 (
As shown in bl, the quartz basket 3 is taken out from the heated portion of the furnace core tube 2 by the straight movement of the drive unit 3C, and the semiconductor wafer 4 is cooled by the cooling gas without being oxidized.

When the temperature of the semiconductor wafer 4 reaches a temperature at which it is not oxidized,
The quartz basket 3 is rotated by half a rotation by the rotational operation of the driving part 3c, the cover part 2a and the basket cover 3e are overlapped, and the semiconductor wafer 4 is taken out, thereby completing the heat treatment process.

In this way, the semiconductor wafer 4 is surrounded by the cover part 2a and the basket cover 3e, and the inert gas is introduced from the cooling gas inlet 3d to cool the semiconductor wafer 4, so that the temperature of the furnace core tube 2 can be lowered. Since the semiconductor wafer 4 can be cooled in a short time without being oxidized, the processing capacity of the heat treatment furnace can be significantly improved.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the shape of the furnace core tube and the structure of the quartz basket are changed, and the function of the drive section of the quartz basket is changed to cool the processed material in a short time. It is possible to provide a heat treatment furnace which has advantages such as being able to perform heat treatment efficiently and without degrading the quality of the object to be treated, and which can be expected to have significant economical and reliability improvement effects.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a schematic structure of a heat treatment furnace according to an embodiment of the present invention. FIG. 2 is a diagram showing a schematic structure of a quartz basket according to an embodiment of the present invention. FIG. 3 is a diagram showing a schematic structure of a quartz basket according to an embodiment of the present invention. Fig. 4 is a side sectional view showing the arrangement of a conventional heat treatment furnace and a quartz basket. In the figure, l is the heater, 2 is the furnace core tube, 2a is the cover, 2b is the processing gas inlet, 3 is the quartz basket, 3a is the base, 3b is the wafer holding part, 3c is the drive part, 3d is the cooling gas introduction 3e is a basket cover 4 is a semiconductor wafer,
shows. fbl Bottom view A diagram showing a schematic structure of a heat treatment furnace according to an embodiment of the present invention Figure +a+ A diagram showing a Kado processing state fBL A diagram showing a cooling state Figure (al Top view ω) Side sectional view An embodiment according to the present invention Diagram showing the schematic structure of a quartz basket. Diagram between side cross-sections showing the arrangement of a conventional heat treatment furnace and a quartz basket.

Claims (1)

[Scope of Claims] A heat treatment furnace for heat-treating a material to be treated (4) in a furnace core tube (2), comprising a part of the tube wall in addition to the heated portion of the furnace core tube (2). An extended cover part (2a) is provided, the object to be processed (4) is mounted thereon, a basket cover (3e) surrounding the object to be processed (4) is provided, and a cooling gas inlet (2a) is provided.
3d) and a drive section (3c) having linear and rotational functions.