JPS63293923A - Processing equipment - Google Patents

Abstract

PURPOSE:To make processing state uniform all over a material to be processed, by rotating a jig retaining a group of materials to be processed in a processing chamber, around a center line parallel with the center line of the processing chamber, said jig being constituted so as to retain a plurality of materials to be processed arranged in parallel and concentric manner. CONSTITUTION:A jig 11 retaining, in a concentric manner, a plurality of wafers 4 arranged in a line, is held in the longitudinal direction by retaining axes 16, 16 that is, in the manner in which the direction of the arranged wafers becomes horizontal. When the jig 11 is set at a prescribed position, it is rotated around the center line of a process tube 1, by a rotation driving equipment 20. After the carrying, the inside of the process tube 1 is exhausted from an exhausting vent 7, and the temperature in the inside of the process tube 1 is raised by a heater 2. When the temperature reaches a specified value, oxygen gas 8 is introduced into the process tube 1 from an introducing inlet 9. An oxide film is uniformly formed on the whole part of the wafer 4, by the introduced oxygen gas 8.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to processing technology, and in particular, to a technology in which a gas is introduced into a processing chamber heated to a high temperature to perform processing on an object to be processed. The present invention relates to a technique that can be effectively used to form an oxide film on a wafer in device manufacturing.

[Conventional technology]

In the manufacture of semiconductor devices, as a device for forming oxide films on wafers, a group of wafers are placed in a row on a boat as a heat treatment jig and are housed in a process tube. Some wafers are configured to form an oxide film on the wafer by heating the wafer to a temperature of 100.degree. C. and introducing oxygen gas at room temperature into the process tube.

An example of the oxide film formation technology is given in "Electronic Materials November 1984 Special Edition" published by Kogyo Research Association Co., Ltd.
There are pages 39 to 44, published on January 20, 1980.

[Problem that the invention seeks to solve]

In such oxide film forming equipment, oxygen gas is introduced into the process tube at room temperature, so the film thickness within each wafer held upright in the port is thicker at the top and thinner at the bottom, resulting in an uneven film thickness distribution. The inventors have discovered that there is a problem in that the film becomes non-uniform.

An object of the present invention is to provide a processing apparatus that can uniformize the processing state throughout the object to be processed.

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]

A summary of typical inventions disclosed in this S is as follows.

In other words, a jig configured to hold a plurality of workpieces parallel to each other and concentrically is placed parallel to the center line of the processing chamber while holding a group of workpieces in the processing chamber. It is configured to rotate around a line.

[Effect]

According to the above-mentioned means, even if the temperature distribution in the processing chamber becomes uneven, the group of objects to be processed is rotated within the processing chamber, so that each part within the object to be processed comes into contact with the uneven temperature distribution. Opportunities to do so are approximately equal. As a result, the treatment by the introduced gas promoted by the heat in the treatment chamber is uniformly performed over the entire surface of the object to be treated.

Embodiment C] FIG. 1 is a longitudinal sectional view showing an oxide film forming apparatus which is an embodiment of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, FIGS. 3 and 4. and FIG. 5 are film thickness distribution diagrams for explaining the thickening effect.

In this embodiment, the oxide film forming apparatus includes a process tube l formed of quartz glass or the like into a substantially cylindrical shape, and this process tube l is heated by a heater 2 provided outside. There is. A furnace port 3 is formed at one end opening of the process tube 1 for loading and unloading a plurality of wafers 4 as processing objects in a lined manner into a jig (to be described later), and the furnace port 3 is opened and closed by a cap 5. It is now possible to do so. Further, a cover 6 larger than the cap 5 is disposed outside the furnace mouth 3 so as to cover the furnace mouth 3 and the cap 5, and this cover 6 is movable back and forth concentrically with the process tube l. It is configured. An exhaust lower is provided near the furnace mouth 3, and the inside of the process tube 1 is exhausted by this exhaust lower. A gas inlet 9 is provided at the other end of the process tube 1 for introducing oxygen gas 8 as an oxidizing agent into the process tube l, and this inlet 9 is connected to an oxygen gas supply device such as an oxygen generator. connected to a power source (not shown).

The jig 11 is made of quartz glass and includes a pair of end plates 12 and three holding members 13 installed between the end plates 12 and 12, respectively. The three holding members 13 are arranged at the apex and both base corners of a substantially isosceles triangle, and both end plates 12 are arranged at right angles to both end surfaces of the holding members so as to cover the space formed by these holding members 13. It is placed and fixed. And a holding member arranged at the apex.

The first holding member 13a (hereinafter referred to as the first holding member 13a) is removably attached to both end plates 12. In this first holding member 13a, a plurality of grooves 1114a are arranged at approximately equal intervals in the longitudinal direction and are carved so as to open opposite to the base of an isosceles triangle, and these grooves 142 are mutually arranged. aligned parallel and perpendicular to the center line,
and is formed at a constant depth.

Holding members arranged at both bottom corners (hereinafter referred to as second and third holding members 13b and 13C) are fixedly installed on both end plates 12.

These holding members 13b and 13c have a plurality of second grooves 14.
b and the third groove 114c in the longitudinal direction of the first groove 133.
The grooves 14b and 14c are arranged so as to match the grooves 14b or 14c on the opposite side, respectively, and are carved so as to open opposite to the grooves 14b or 14c on the opposite side.
4b and 14c are aligned parallel to each other,
Together with the first groove l4a, it is formed so as to constitute one plane perpendicular to the center line of the jig 11.

The jig 11 configured in this way is arranged concentrically with the center line of the process tube 1 and is configured to be rotated. That is, both end plates 12.12
Support shafts 15.16 are fixedly arranged on the center line on the outer end surface of the support shaft 15.16, and both support shafts 15.16 pass through the cap 5, the cover 6, and the gas inlet 9, respectively. The two support shafts 15 and 16 protruding to the outside of the tube l are rotatably and slidably supported by support devices W17 and 18 respectively disposed on both sides of the process tube l. 15.16 and cap 5,
A seal member 19 is provided between the cover 6 and the gas inlet 9.
are appropriately arranged and interposed, and both support shafts 15 and 16 are maintained airtight with respect to the process tube 1 by these seal members 19. A rotary drive device 20 consisting of a reduction gear mechanism or the like is installed on one side of the process tube 1, and this device 20 is configured to rotate the jig 11 in conjunction with the rotating shaft 15.

Next, a method of using the oxide film forming apparatus and jig according to the above structure and its operation will be explained.

The wafers 4 to be subjected to film formation are pulled out of the process tube 1 and held in the jig 11 in a line. That is, the wafer 4 is held in the first holding member 13a.
With the second and third holding members 13b and 13 removed,
The first holding member 13a is then attached between the end plates 12 and 12, and the first holding member 13a is inserted between the two end plates 12, The approximately central position between the second and third grooves of the wafer 4 is engaged with the first groove 14a of the first holding member 13a.Thereby, the wafer 4 is held between the three holding members from three directions. Therefore, the wafers 4 are set and held so that they do not fall off even when the jig 11 is rotated.Also, when the plurality of wafers 4 are held in the jig 11, their outer peripheral edges are aligned and they are concentric. and are arranged parallel to each other.

In this state, the jig 11, which holds a plurality of wafers 4 in a line and concentrically aligned, is mounted on the support shaft 15.
Supported by

The jig 11 supported between the support shafts 15 and 16 is moved horizontally and carried into the processing chamber from the furnace opening 3 of the process tube 1, and remains supported by both support shafts 15 and 16. It is located approximately in the center of the processing chamber. Accordingly, the furnace mouth 3 is sealed by the camp 5 and the cover 6. When the jig 11 is placed at a predetermined position, the jig 11 is rotated around the centerline of the process tube 1 by the rotation drive device 20 .

After loading, the inside of the process tube 1 is exhausted from the exhaust lower, and then the temperature inside the process tube 1 is raised by the heater 2 until the temperature inside the process tube 1 reaches a predetermined temperature (for example, 700°C to 1100°C). At the point where the oxygen gas 8 is supplied from the supply source, it is introduced into the process tube 1 through the inlet 9. Then, an oxide film is uniformly formed over the entire wafer 4 by the introduced oxygen gas 8.

By the way, when oxygen gas at room temperature is introduced into the process tube, the temperature distribution inside the process tube becomes non-uniform at the beginning of the introduction. That is, since the oxygen gas at the initial stage of introduction is at a low temperature, it stagnates in the lower part of the process tube, and the heated oxygen gas moves to the upper part. As a result of (1), the formation of an oxide film is promoted by the heated oxygen gas, and as shown in Figure 3, the film thickness tends to become thicker at the top of the wafer and thinner at the bottom. The film thickness distribution within the wafer becomes uneven.

However, in this embodiment, since the jig 11 is rotated around the center line within the process tube l, the distribution of the oxide film is different from the wafer l as shown in FIG. 4 or FIG. It is formed approximately uniformly throughout.

That is, the distribution of oxygen gas 8 and the process tube l
Although the temperature distribution inside the tube is uneven in the upper and lower portions, as the jig 11 rotates, the individual wafers 4 held therein also rotate around the center line of the process tube l. Each part will have equal opportunity to contact the non-uniform distribution. Therefore, the formation process of the oxide film due to the contact becomes approximately uniform, and as a result, the film thickness distribution becomes approximately uniform within the wafer. Incidentally, the concentric non-uniform film thickness distribution as shown in Figure 4 or Figure 5 can be easily corrected by optimizing the gas supply and heater temperature control. .

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

(1) By rotating a jig holding multiple wafers around the center line of the process tube, even if the temperature distribution inside the process tube is uneven, each part of the wafer is Since contact occurs with equal opportunity, a uniform oxide film can be formed throughout the wafer.

(2) By applying uniform processing to the entire wafer, the characteristics of the wafer can be made homogeneous, so that the yield can be improved.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the above Examples, and it is possible to make various changes without departing from the gist of the invention. Not even.

For example, the structure of the jig, its support and rotation mechanism, etc. are not limited to those shown in the above embodiments.

Furthermore, although the above embodiments have been described with respect to a horizontal apparatus in which the process tube is installed horizontally, the present invention can also be applied to a vertical apparatus. Although it is not possible to correct the non-uniform temperature distribution between the upper and lower parts of the vertical apparatus, the rotation can equalize the opportunity for contact with the process gas throughout the wafer. Furthermore, in the case of a vertical device, the jig support and rotation mechanism can be simplified.

As the processing gas, not only oxygen gas but also wet oxygen, phosphine, monosilane, etc. may be used.

There are no limitations on the shape, structure, arrangement, etc. of the process tube, exhaust port, gas introduction port, heater, etc., and the object to be processed is not limited to wafers.

In the above explanation, the invention made by the present inventor was mainly applied to the oxide film forming technology, which is the background application field, but the invention is not limited thereto. It can also be applied not only to oxide film forming equipment but also to CVD equipment, epitaxial equipment, etc.
The present invention can be applied to all processing apparatuses in which gas is introduced into at least a heated processing chamber.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

By rotating a jig holding multiple objects to be processed around the center line of the processing chamber, even if the temperature distribution in the processing chamber is uneven, each part of the objects to be processed is Since contact occurs with equal opportunity, uniform treatment can be applied to the entire interior of the object to be treated.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an oxide film forming apparatus which is an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1, FIGS.
FIG. 5 and FIG. 5 are film thickness distribution diagrams for explaining the effect. 1... Process tube (processing chamber), 2... Heater, 3... Furnace mouth, 4... Wafer (processed object), 5...
・Cap, 6...Cover, 7...Exhaust port, 8...
・Oxygen gas (processing gas), 9...Gas inlet, 11.
... Jig, 12... End plate, 13a, 13bS L3c
m holding member, 14a, 14b, 14c--retaining groove,
15.16--Spindle, 17.18--Support device, 1
9... Seal member, 20... Rotation drive device R0

Claims (1)

[Claims] 1. A jig configured to hold a plurality of objects to be processed parallel to each other and concentrically holds a group of objects to be processed within the processing chamber. A processing device configured to rotate around a line parallel to the center line of the processing device. 2. The processing apparatus according to claim 1, wherein the rotation center of the jig is set to substantially coincide with the center line of the processing chamber and the center line of the group of objects to be processed. 3. The processing apparatus according to claim 1, wherein the processing chamber is configured such that its longitudinal direction is horizontal. 4. The processing apparatus according to claim 1, wherein the processing chamber is configured such that its longitudinal direction is vertical.