JPH0878334A - Wafer treatment apparatus - Google Patents

Abstract

PURPOSE: To obtain a wafer treatment apparatus by which a gas is supplied uniformly to respective wafers by installing a flow-straightening plate, which prevents the spread of the flow of the gas disturbed by a turntable by installing a partition plate and by which the respective wafers can be treated with an extremely high wafer-treatment efficiency and under a uniform condition. CONSTITUTION: A plurality of turntables 12 are arranged inside a treatment container 10, and susceptors 36 are mounted on the respective turntables 12. The respective turntables 12 are divided by upper partition plates 30 and lower partition plates 28. The inside of the container 10 is divided into two upper and lower chambers by a flow-straightening plate 14, and a gas is introduced into the chamber on the upper side from gas introduction ports 22. The gas is discharged from evacuation ports 24 in the bottom face of the container 10.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an apparatus for processing a wafer such as a silicon wafer.

[0002]

2. Description of the Related Art As a wafer processing apparatus used for manufacturing epitaxial silicon wafers, surface processing of silicon wafers, etc., there is a wafer processing apparatus provided with a turntable in a processing container. In this case, it is known that many wafers are arranged on a turntable in multiple stages via spacers in order to improve the wafer processing efficiency (for example, Monthly Semiconductor World 1988-5, P.39). .

[0003]

When the wafers are stacked and processed in multiple stages as described above, it is difficult to process each wafer uniformly because the gas is not uniformly applied to each wafer. Further, the gas or particles generated from the wafer may come into contact with other wafers to affect them.

[0004]

A wafer processing apparatus according to claim 1 is a wafer processing apparatus in which a turntable for mounting a wafer susceptor is installed in a processing container, and a plurality of the turntables are installed. By disposing a straightening plate above the turntable in the processing container, the inside of the processing container is divided into upper and lower chambers, a gas inlet is provided in the upper chamber, and a gas outlet is provided in the lower chamber. It is characterized by being provided.

According to a second aspect of the present invention, in the wafer processing apparatus according to the first aspect, a horizontal partition is provided at a level slightly lower than the turntable, and a rotary shaft of the turntable is inserted into the horizontal partition and the horizontal partition is inserted horizontally. It is characterized in that an opening for guiding gas from the upper side to the lower side of the partition wall is provided.

A wafer processing apparatus according to a third aspect is the wafer processing apparatus according to the second aspect, wherein the opening has a larger diameter than the turntable, and the wafer processing apparatus further raises and lowers a table for moving the turntable up and down through the opening. An apparatus and a horizontal moving device for moving the horizontal partition into and out of the processing container are provided.

According to a fourth aspect of the present invention, in the wafer processing apparatus according to any one of the first to third aspects, a partition plate is provided between the turntables.

A wafer processing apparatus according to a fifth aspect of the present invention is the wafer processing apparatus according to any one of the first to fourth aspects, wherein the exhaust ports are provided below each turntable, and the exhaust amount is individually provided to each exhaust port. It is characterized in that an adjustable exhaust amount adjusting mechanism is provided.

[0009]

In the wafer processing apparatus of the first to fifth aspects, since a plurality of turntables are arranged, a plurality of wafers can be processed simultaneously. The gas is introduced into the chamber above the straightening vanes and uniformly flows down toward each turntable by the straightening vanes. By placing only one wafer on each turntable, the gas can be uniformly contacted with the wafer on each turntable.

According to another aspect of the wafer processing apparatus of the present invention, the horizontal partition is provided below the turntable, and the horizontal partition is provided with an opening below each turntable. A forced exhaust stream is formed that wraps around and flows into the opening.

The reaction gas and particles generated on the surface of the wafer on the turntable are conveyed to this exhaust flow and are quickly discharged, so that they are prevented from diffusing into the entire processing container.

In the wafer processing apparatus of claim 3, the turntable is lowered below the horizontal partition wall,
The wafer susceptor is placed on a horizontal partition and carried into the processing container, and each wafer susceptor is arranged above the turntable. Then, by raising the turntable,
The wafer susceptor is placed on each turntable. In this state, gas is introduced into the container to process the wafer on the wafer susceptor.

After the processing is completed, the turntable is lowered and the wafer susceptor is placed on the horizontal partition. Then, by moving the horizontal partition to the outside of the container, the wafer susceptor on which the wafer is placed can be carried out of the container.

In the wafer processing apparatus of the fourth aspect, it is possible to prevent the gas flow downward from the flow straightening plate in the lateral direction and to cause the gas flow to flow straight down toward the wafer. Further, the gas flow disturbed by the turntable can be prevented from spreading laterally.

As a result, the reaction can proceed uniformly over the entire surface of the wafer, and a thin film having a uniform film thickness can be formed.

In the wafer processing apparatus of the fifth aspect, by individually adjusting each exhaust adjusting mechanism, it is possible to equalize the airflow state diffused to the wafer on each turntable.

[0017]

Embodiments will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a wafer processing apparatus according to an embodiment,
FIG. 2 is a sectional view taken along the line II-II in FIG.

In this wafer processing apparatus, a plurality of (six in this embodiment) turntables 12 are arranged in a processing container 10, and the current plate 1 is provided above the turntables 12.
By arranging 4 horizontally, the inside of the processing container 10 is divided into upper and lower chambers. As the current plate, various things such as a mesh and a punching plate can be adopted.

The processing container 10 includes a case lower 16 and
A case upper 18 and a transparent panel 20 provided on the upper side of the case upper 18, and a gas inlet 22 is provided above the case upper 18 above the current plate 14.
Is provided. Also, on the bottom of the case lower 16,
A total of six gas exhaust ports 24 are provided.

The rotary shaft 2 is provided at the center of the gas exhaust port 24.
6 are arranged in the vertical direction, and each rotary shaft 26 is pivotally supported by a bearing (not shown) and can be rotationally driven by a drive device (not shown) capable of independently controlling rotation. . The turntable 12 is fixed to the upper end of the rotary shaft 26.

A partition plate extending in the vertical direction is arranged so as to partition the turntables 12 from each other.
In this embodiment, as the partition plates, a lower partition plate 28 standing upright from the bottom surface of the case lower 16 and an upper partition plate 30 vertically extending from the lower surface of the rectifying plate 14 are provided.

A guide cylinder 3 is provided below the gas exhaust cylinder 24.
2 are connected in series, and the lower end of the guide cylinder 32 is connected to an exhaust pump (not shown) via an exhaust pressure adjusting tamper 34 and a duct 38.

An infrared lamp (not shown) is arranged above the transparent panel 20, and a wafer (not shown) placed on the wafer susceptor 36 on the turntable 12 by infrared rays emitted from the infrared lamp. Can be heated.

In order to process a wafer using the wafer processing apparatus thus constructed, the case upper 18 is removed, and the wafer susceptor 36 on which the wafer is mounted is set on the turntable 12. Next, after mounting the case upper 18 on the case lower 16, gas is introduced from the gas inlet 22 and the wafer is heated by the infrared lamp. The gas introduced from the gas introduction port 22 into the chamber above the straightening vane 14 is evenly distributed toward the turntables 12 by the straightening vane 14 and flows down. The gas reacted on the wafer surface is discharged together with the unreacted gas through the gas exhaust port 24, the guide cylinder 32, the damper 34, and the duct 38.

According to such a wafer processing apparatus, a plurality of wafers can be processed at the same time in one processing container 10, and the wafer processing efficiency becomes extremely high. In this wafer processing apparatus, one wafer is placed on each turntable 12, and the gas is evenly distributed and supplied to each wafer by the rectifying plate 14. Can be processed at.

In addition, in this embodiment, the partition plate 2
Since the turntables 12 are separated from each other by 8 and 30, and a damper 34 is provided in each gas exhaust passage for adjusting the exhaust pressure independently, gas is evenly distributed on the wafers on each turntable 12. The gas flow conditions can be controlled so that they come into contact with each other. Therefore, each wafer can be processed under the same conditions.

Further, by providing the partition plates 28 and 30, it is possible to prevent the gas flow disturbed by one wafer susceptor 36 from affecting the periphery of the adjacent wafer susceptor 36. Further, by providing the upper partition plate 30, it is possible to cut the lateral flow component (vector component) of the gas that has passed through the straightening plate 14, and it is possible to flow the gas straight down toward the wafer. The reaction can proceed under uniform conditions over the entire surface of the wafer. As a result, a thin film with less variation in film thickness can be formed on the surface of the wafer.

In the embodiment shown in FIGS. 1 and 2, both the upper partition plate 30 and the lower partition plate 28 are provided, but only one of the partition plates may be provided. Further, in the present invention, the partition plates 28 and 30 may be omitted.

FIG. 3 is a vertical sectional view of a wafer processing apparatus according to another embodiment of the present invention. In this embodiment, the partition plate 28,
30 is omitted. In this embodiment, a horizontal partition 40 is provided slightly below the turntable 12. The horizontal partition 40 is provided with an opening 42 corresponding to each turntable 12, and the rotary shaft 26 is inserted into the opening 42. The diameter of the opening 42 is slightly smaller than the diameter of the wafer susceptor 36.

The other construction of this embodiment is the same as that of the embodiment shown in FIG. 1, and the same reference numerals indicate the same parts.

Also in this embodiment, the gas introduced from the gas inlet 22 is uniformly supplied to the wafer on each turntable 12 by the straightening plate 14, and the uniform reaction proceeds on the surface of each wafer. In the present embodiment, a forced exhaust flow is formed around the periphery of the turntable 12 and drawn into the opening 42. Therefore, the gas generated by the reaction on the wafer surface and the gas generated by the etching action on the wafer surface are introduced into the gas. Because the gas containing impurities that comes out will be quickly discharged by this forced exhaust flow,
Impurity contamination on the wafer surface is reliably prevented, and a high-purity thin film can be formed. Further, it is possible to reduce variations in the resistance distribution within the wafer due to autodoping.

FIG. 4 is a vertical sectional view of a wafer processing apparatus according to still another embodiment of the present invention. In the wafer processing apparatus of this embodiment, the upper partition plate 30 and the lower partition plate 28 are provided, the size of the opening 42 is made to allow the turntable 12 to pass through, and an elevating device (not shown) for the turntable 12 is provided. It is provided. Further, in the present embodiment, the horizontal partition wall 40 can be loaded and unloaded through the loading / unloading device (rotlock) 46 provided on the side surface of the processing container 10, and the wafer susceptor 36 on which the wafer is placed can be placed in the horizontal partition wall 40. The horizontal partition can be taken in and out of the processing container 10 while being placed on the partition 40.

As shown in FIG. 5, a non-circular (a cross shape in this embodiment) convex portion 50 is provided on the upper surface of the turntable 12, and the convex portion 50 is formed on the bottom surface of the wafer susceptor 36. Recesses (not shown) having the same shape are provided, and the protrusion 50 and the recesses are fitted to each other, so that the rotational force of the turntable 12 can be reliably ensured.
Can be transmitted to.

To charge a wafer in this wafer processing apparatus, the turntable 12 is lowered to below the horizontal partition 40, and then the horizontal partition 40 is moved to the outside of the processing container 10. Then, the wafer susceptor on which the wafer is placed is placed on the opening 42 of the horizontal partition. Then, the horizontal partition 40 is moved into the processing container 10. After that, the turntable 12 is moved upward and the turntable 12 is moved.
The wafer susceptor 36 is placed on top. At this time, by raising the turntable 12 while rotating it at a predetermined speed, the convex portion 50 can be reliably fitted into the concave portion of the wafer susceptor 36.

The rotary shaft 26 of the turntable 12
Is configured to be accurately moved up and down by a predetermined stroke by a sensor (not shown) provided in the lifting device.

The wafer susceptor 36 is the turntable 12
The wafer susceptor 36 is placed on the horizontal partition wall 4
After rising from 0 to a predetermined distance above, the turntable 12 is stopped from rising. Then, the wafer placed on the wafer susceptor 36 is processed.

After the processing of the wafer is completed, the turntable 12 is lowered and the wafer susceptor 36 is moved to the horizontal partition wall 4.
Put it on 0. The turntable 12 is lowered until it is separated from the wafer susceptor 36. Then, the horizontal partition 40 is pulled out of the processing container 10. In addition,
The horizontal partition 40 having the same shape is waiting outside the processing container 10 with the wafer susceptor charged with the wafer, and the horizontal partition 40 that has been in the processing container 10 until then is pulled out to the outside of the processing container 10. After that, a new horizontal partition 40 is introduced into the processing container 10 in place of this, and the wafer is processed again.

As described above, according to the apparatus of this embodiment, the wafer can be taken in and out very easily and quickly. In addition, since it is not necessary to open the entire processing container when loading and unloading the wafer, gas replacement and wafer loading and unloading can be performed while keeping the temperature inside the processing container 10 at a high temperature (for example, 500 ° C.). It is possible to prevent the deterioration of the quality of the wafer surface layer due to the adhesion of water and the adsorption of water.

In each of the above embodiments, the wafer is heated by the infrared lamp, but in the present invention, a heating mechanism other than the infrared heating lamp system may be used. For example, a resistance heating mechanism or an electromagnetic induction heating mechanism can be adopted. The apparatus of the present invention is suitable for application to an epitaxial growth apparatus, but it is obvious that it can be used as another wafer processing apparatus.

[0040]

As described above, according to the wafer processing apparatus of the first to fifth aspects, a plurality of wafers can be processed at the same time, and the wafer processing efficiency becomes extremely high. Also,
The gas is uniformly supplied to each wafer by the action of the straightening plate, and the reactions in each wafer can be made uniform.

According to the wafer processing apparatus of claims 2 and 3,
The reaction gas and particles generated on the wafer surface can be quickly discharged to the outside of the processing container, and a high-purity thin film can be formed. According to the wafer processing apparatus of the third aspect, the wafer can be taken in and out very easily and quickly, and the wafer processing efficiency can be remarkably improved. In addition, since it is not necessary to open the entire inside of the processing container when loading and unloading the wafer, it is possible to perform gas replacement and loading and unloading of the wafer while keeping the temperature inside the furnace at a high temperature, and it is possible to obtain a high quality processed wafer .

According to the wafer processing apparatus of the fourth aspect, the supply of the gas to each wafer becomes more uniform, and the influence of the turbulence of the gas flow can be significantly reduced.
As a result, the accuracy of the film thickness on the wafer surface can be improved, and the difference in film thickness between the wafers can be made extremely small.

According to the wafer processing apparatus of the fifth aspect, the processing conditions for each wafer can be made uniform with high accuracy.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a wafer processing apparatus according to an embodiment.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a vertical cross-sectional view of a wafer processing apparatus according to another embodiment.

FIG. 4 is a vertical sectional view of a wafer processing apparatus according to still another embodiment.

5 is a perspective view of a turntable and a wafer susceptor of the apparatus of FIG.

[Explanation of symbols]

 10 processing container 12 turntable 14 straightening plate 22 gas inlet port 24 gas exhaust port 26 rotary shaft 28 lower partition plate 30 upper partition plate 34 exhaust pressure adjusting damper 36 wafer susceptor 40 horizontal partition wall 42 opening

Claims (5)

[Claims] 1. A wafer processing apparatus in which a turntable for mounting a wafer susceptor is installed in a processing container, and a plurality of the turntables are installed, and a current plate is arranged above the turntable in the processing container. The wafer processing apparatus is characterized in that the inside of the processing container is divided into upper and lower chambers by providing the above, and a gas inlet is provided in the upper chamber and a gas outlet is provided in the lower chamber. 2. The horizontal partition is provided at a level slightly lower than the turntable, and the rotary shaft of the turntable is inserted into the horizontal partition, and the horizontal partition extends from the upper side to the lower side. A wafer processing apparatus having an opening for introducing gas. 3. The wafer processing apparatus according to claim 2, wherein the opening has a diameter larger than that of the turntable, and the wafer processing apparatus further includes a table lifting device for vertically moving the turntable through the opening, and the horizontal partition. And a horizontal moving device for moving the horizontal partition wall into and out of the processing container. 4. The wafer processing apparatus according to claim 1, wherein a partition plate is provided between the turntables. 5. The exhaust amount adjusting mechanism according to claim 1, wherein the exhaust ports are provided below the respective turntables, and the exhaust amounts are individually adjusted to the exhaust ports. A wafer processing apparatus, which is provided.