JP2008235830A - Vapor-phase growing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vapor-growing apparatus in which the corrosion of metal parts, such as a stainless, can be reduced and which is easily maintained. <P>SOLUTION: A vapor growth device 1 is provided with an annular metal base ring 10; and an upper dome 8 and a lower doom 9 made of quartz which constitute a chamber 2 by sandwiching the base ring 10 from the upper and lower sides. In the interior of the chamber 2, the vapor growth device 1 is provided with an upper liner 16 and a lower liner 17; and a susceptor 4, in which a wafer W for performing the vapor phase growth of an epitaxial layer is laid in a top surface thereof. In order to correct the difference of the volumetric change in the reactor generated between an upper reactor 3 and an lower reactor 5, by covering an inner wall surface of the base ring 10 which constitutes a part of the inner wall surface of the reactor with a chamber shield 15, which consists of a quartz glass plate, a concave part 17b for adjusting the volume in the reactor is provided in the lower liner 17. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vapor phase growth apparatus for generating an epitaxial layer on a wafer, and more particularly to the structure of a vapor phase growth apparatus that is easy to maintain.

A wafer used as a raw material wafer for manufacturing a semiconductor device is a single crystal semiconductor ingot grown by the Czochralski method (CZ method) or the floating zone melting method (FZ method), and the outer periphery of the grown semiconductor ingot is It is formed by grinding with a cylindrical grinder or the like and slicing with a wire saw in a slicing step.
Thereafter, the wafer peripheral portion is chamfered in a chamfering process, and after a flattening process and an etching treatment process in a lapping process, primary polishing and secondary polishing are performed, and then wafer cleaning is performed to obtain a mirror surface wafer.

Further, a technique for manufacturing a silicon wafer having a desired resistivity without crystal defects by growing a single crystal layer of silicon having the same crystal orientation on a mirror wafer substrate is known.
This single crystal layer of silicon is an extremely thin layer having a thickness of about several μm in the case of a wafer having a diameter of 200 mm and a thickness of 0.75 mm, for example, and is generally called an epitaxial layer. As a vapor phase growth apparatus used for the production of this epitaxial layer, there is a single wafer type vapor phase growth apparatus called a single wafer type that processes silicon wafers one by one (see, for example, Patent Documents 1 to 6).

FIG. 8 is a longitudinal sectional view schematically showing a single wafer vapor phase growth apparatus.
In this vapor phase growth apparatus 31, a susceptor 4 that normally supports only one wafer W horizontally is provided in the chamber 2. In the chamber 2, an annular base ring 10 is sandwiched from above and below by an upper dome 8 and a lower dome 9 made of transparent quartz, and a closed space inside is a reaction furnace. In order to maintain airtightness, an O-ring 11 is sandwiched between the upper dome 8 and the base ring 10, and an O-ring 12 is sandwiched between the lower dome 9 and the base ring 10.

  In order to grow an epitaxial layer on the wafer W, a reactive gas (raw material gas and carrier gas) is flowed along the upper surface of the wafer W, and the wafer W supported on the susceptor 4 is heated to a high temperature of about 1000 to 1200 ° C. It needs to be heated. Therefore, heat sources 6 and 7 for heating the reaction furnace are provided above and below the chamber 2. An infrared lamp or a far-infrared lamp can be used as the upper and lower heat sources 6 and 7, and the susceptor 4 and the wafer W are heated by radiant heat from the upper and lower sides of the chamber 2.

Openings 10a and 10b are formed on the left and right sides of the chamber 2. The source gas and the carrier gas flow into the upper reaction furnace 3 from one gas inlet 10a, and the reacted gas and the gas from the other gas outlet 10b. Carrier gas is discharged. Further, hydrogen H ₂ is supplied as a purge gas from below the chamber 2, and the purge gas filled in the lower reaction furnace 5 is discharged from the gas discharge port 10 b through the purge gas discharge hole 17 a provided in the lower liner 17.
As the source gas, chlorosilane-based gas such as trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ is generally used. These gases are introduced into the upper reaction furnace 3 together with hydrogen H _{2 as} a carrier gas, and an epitaxial layer is generated on the wafer surface by a thermal CVD reaction.

The susceptor 4 has a disk shape, and its diameter is larger than that of the wafer W. The susceptor 4 is disposed so that the plate surface is horizontal, and a circular recess for storing a wafer in which the wafer W is stored is provided on the upper surface of the susceptor 4. The susceptor 4 serves as a soaking plate that keeps the temperature of the entire wafer uniform when the wafer W is heated.
The susceptor 4 rotates in the plane parallel to the plate surface of the wafer W about the vertical axis during the epitaxial layer growth processing operation.

A susceptor support 25a is in contact with the lower surface of the susceptor 4 to support the susceptor 4 from below. Three support arms 25 (only two are shown in FIG. 8) are provided on the top of the susceptor support shaft 21, and each has a susceptor support 25a at the tip. Each support arm 25 is arranged radially from the center of the susceptor support shaft 21 so that each support arm 25 forms an angle of 120 ° when viewed from above.
The susceptor 4 is placed on the susceptor support 25a so that the center of the susceptor 4 and the axis of the susceptor support shaft 21 coincide with each other, and the susceptor 4 rotates stably without being shaken by the rotation of the susceptor support shaft 21. . The rotation to the susceptor support shaft 21 is given by a rotation driving motor (not shown).
The susceptor support shaft 21 and the support arm 25 are made of high-purity transparent quartz so as not to block light from the lower heat source 7.
JP 2003-13397 A JP 2003-1442412 A JP 2003-197532 A JP 2003-229370 A JP 2004-637779 A JP 2003-124287 A

In general, in the vapor phase growth apparatus as described above, the base ring 10 is made of a metal such as stainless steel.
The base ring 10 is corroded by contact with a chlorosilane-based gas such as trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ used as a raw material gas. Once a stainless steel part is corroded, there is no means to prevent corrosion during wafer processing, and the corroded iron oxide or other metal powder is thermally diffused into the wafer, resulting in a resistance value or SR profile (internal resistance steepness) of the silicon wafer. Is damaged.

Furthermore, a chlorosilane-based gas such as trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ used as a raw material gas undergoes a chemical reaction, and a Si _x —H _y —Cl _z compound is generated as a side reaction product. The Si _x -H _y -Cl _z compound, which is a side reaction product, tends to deposit particularly in the vicinity of the gas inflow passage 18 and the gas exhaust passage 19 formed by the upper liner 16 and the lower liner 17. Therefore, more side reaction products are deposited near the gas inlet 10a and the gas outlet 10b than the other parts.
FIG. 6 is an enlarged view showing the vicinity of the gas outlet 10b of FIG. As shown in FIG. 6, the Si _x —H _y —Cl _z compound is deposited as a side reaction product 32 (indicated by a chain line) by adhering to the upper liner 16 and the lower liner 17 which are gas flow paths. If the deposited side reaction product 32 is peeled off during the processing of the wafer W, it causes wafer contamination. Therefore, it is necessary to periodically clean the upper liner 16 and the lower liner 17 with hydrofluoric acid to remove the deposit.

  FIG. 7 is an enlarged view showing the vicinity of the gas discharge port 10b after cleaning with hydrofluoric acid. Since the upper liner 16 and the lower liner 17 are made of opaque quartz, they are eroded by cleaning with hydrofluoric acid. Therefore, as the hydrofluoric acid cleaning is repeated, the thickness gradually decreases and a gap 33 is formed between the base ring 10 and the base ring 10 as shown in FIG. Then, the raw material gas enters the gap 33 and further accelerates the corrosion of the base ring 10.

In addition, the Si _x —H _y —Cl _z compound produced as a side reaction product also accumulates in the vicinity of the gap 33 and the gas inlet 10 a and the gas outlet 10 b of the base ring 10. As described above, by-products are accumulated inside the upper reaction furnace 3, so that they must be periodically cleaned to remove them.
At that time, it is necessary to open the inside of the chamber 2 to the atmosphere, and the side reaction product fixed to the surface of the stainless steel part due to the inflow of the atmosphere is exposed to moisture in the atmosphere.
As a result, the Si _x -H _y -Cl _z compound, which is a side reaction product, is hydrolyzed to produce HCl HCl. This hydrochloric acid HCl further corrodes the stainless steel part.

In particular, since a large amount of Si _x -H _y -Cl _z compound as a side reaction product tends to be deposited in the vicinity of the gas inflow passage 18 and the gas exhaust passage 19, the gas is released when the chamber 2 is opened to the atmosphere. Corrosion of the base ring 10 at the inlet 10a and the gas outlet 10b is significant.
The corroded stainless steel becomes a gel and adheres to the vicinity of the gas inlet 10a and the gas outlet 10b of the base ring 10 and causes further contamination. Further, this gel-like deposit (deposition) needs to be removed using a spatula such as a scraper, which causes a long time for maintenance work.

The invention according to the present application has been made in order to solve the above-described problems, and an object of the invention is a structure of a vapor phase growth apparatus that can reduce corrosion of metal parts such as stainless steel. Is to provide.
Another object of the present application is to provide a vapor phase growth apparatus that can suppress the occurrence of deposition and can be easily maintained.

In order to achieve the above object, the first invention according to the present application is:
A support for supporting a workpiece for forming a vapor phase growth layer on at least a part of the surface;
A reactor formed by surrounding the periphery of the support by a plurality of components including metal parts made of metal that can be a contaminant to the vapor phase growth layer or the workpiece;
In a vapor phase growth apparatus comprising:
At least a part of the inner wall surface of the metal part constituting a part of the inner wall surface of the reaction furnace is covered with a substance that does not become a contaminant for the vapor phase growth layer or the workpiece. It is a vapor phase growth apparatus.

The second invention according to the present application is
A wafer support for supporting a wafer for vapor-phase growth of an epitaxial layer on the upper surface;
A reaction furnace formed by surrounding the periphery of the wafer support with a plurality of components including metal parts;
In a vapor phase growth apparatus comprising:
A vapor phase growth apparatus characterized in that at least a part of the inner wall surface of the metal part constituting a part of the inner wall surface of the reactor is covered with a quartz glass plate.

Furthermore, the third invention according to the present application is:
A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
In a vapor phase growth apparatus comprising:
A vapor phase growth apparatus characterized in that at least a part of an inner peripheral wall surface of the base ring constituting a part of an inner wall surface of the reaction furnace is covered with a substance that does not become a contaminant to the epitaxial layer or the wafer. It is.

The fourth invention according to the present application is
4. The vapor phase growth apparatus according to the first or third aspect, wherein the substance that does not become a contaminant is quartz.

Furthermore, the fifth invention according to the present application is:
The metal part has at least one of a gas inlet for supplying gas into the reactor or a gas outlet for discharging gas in the reactor,
In the first or second invention, the at least part of the inner wall surface of the metal part is an inner wall surface adjacent to at least one of the gas inlet or the gas outlet. The vapor phase growth apparatus described.

The sixth invention according to the present application is
The metal part has at least one of a gas inlet for supplying gas into the reactor or a gas outlet for discharging gas in the reactor,
The vapor phase growth apparatus according to the first or second invention, wherein the inner wall surface of at least one of the gas inlet or the gas outlet is covered with quartz.

Furthermore, the seventh invention according to the present application is
A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
In a vapor phase growth apparatus comprising:
In the vapor phase growth apparatus, an inner peripheral wall surface of the base ring constituting a part of an inner wall surface of the reaction furnace is covered with a chamber shield made of a detachable quartz glass plate.

The eighth invention according to the present application is
From the temperature of the reactor and the thermal expansion coefficient of the material constituting the base ring, obtain the expansion dimension of the base ring in a high temperature range,
From the temperature of the reactor and the coefficient of thermal expansion of the material constituting the chamber shield, obtain the expansion dimension of the chamber shield in a high temperature range,
In consideration of the expansion dimensions of both, the chamber shield is formed so that the outer peripheral surface of the chamber shield does not come into contact with the inner peripheral wall surface of the base ring due to thermal expansion during the reaction process of the wafer. A vapor phase growth apparatus according to the seventh invention, characterized in that:

Furthermore, the ninth invention according to the present application is
A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
An upper liner and a lower liner disposed in the reactor;
In a vapor phase growth apparatus comprising:
By covering the inner peripheral wall surface of the base ring constituting a part of the inner wall surface of the reactor with a chamber shield made of a quartz glass plate, the upper reactor and the reactor of the reactor above the susceptor of the reactor In order to correct the difference in the furnace volume change that occurs between the lower reactor and the lower reactor below the susceptor, an adjustment unit for adjusting the furnace volume is provided in at least one of the upper liner and the lower liner. This is a vapor phase growth apparatus characterized by the above.

ADVANTAGE OF THE INVENTION According to this invention, corrosion of metal parts, such as stainless steel used in the reaction furnace of a vapor phase growth apparatus, can be reduced.
In addition, according to the vapor phase growth apparatus of the present invention, it is possible to suppress the accumulation of the side reaction product, so that the maintenance work becomes easy and the yield of the product can be improved.

Next, a vapor phase growth apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view schematically showing a vapor phase growth apparatus according to the present invention. The vapor phase growth apparatus 1 is an apparatus for producing an epitaxial wafer by vapor-phase growing an epitaxial layer on a wafer. FIG. 1 shows an example of a single-wafer type vapor phase growth apparatus that performs vapor phase growth processing for each wafer, but the present invention also applies to a batch type vapor phase growth apparatus that simultaneously processes a plurality of wafers. Can be applied.

In FIG. 1, a vapor phase growth apparatus 1 includes a chamber 2 constituting a reaction furnace, a susceptor 4 disposed in the chamber 2, and a heat source 6 disposed outside the chamber 2 to heat the susceptor 4 and the wafer W from above and below. , 7.
The chamber 2 has an annular base ring 10 sandwiched between the upper dome 8 and the lower dome 9 from above and below, and the inside is a closed space. In the present application, a space above the susceptor 4 of the reaction furnace constituted by the chamber 2 is referred to as an upper reaction furnace 3, and a space below the susceptor 4 is referred to as a lower reaction furnace 5.

In order to maintain airtightness in the chamber 2, an O-ring 11 is sandwiched between the upper dome 8 and the base ring 10, and an O-ring 12 is sandwiched between the lower dome 9 and the base ring 10. As the O-rings 11 and 12, resin-made O-rings having excellent heat resistance are used.
Although FIG. 1 shows an example in which three O-rings 11 and three O-rings 12 are provided, the number of O-rings 11 and O-rings 12 is not necessarily three, and may be three or more or three or less. good. Further, instead of the O-ring, another seal member may be used.

The upper dome 8 has a generally disc shape, and includes a circular flat plate top plate portion 8a and an annular flat plate base portion 8b integrally formed so as to surround the outer periphery thereof. The top plate portion 8a constituting the top plate is made of a transparent quartz plate so as not to block light from the heat source 6, and the base portion 8b constituting the outer peripheral portion is made of an opaque quartz plate thicker than the top plate.
In the present embodiment, the top plate portion 8a is an example of a flat plate, but may be convexly curved toward the outside of the upper reactor 3 or may be curved concavely toward the inside. .
The upper dome 8 can be attached to and detached from the base ring 10, and the maintenance work in the chamber 2 is performed by removing the upper dome 8 from the base ring 10 during maintenance of the reactor.

The lower dome 9 protrudes outward so as to surround the outer periphery of the funnel-shaped bottom plate portion 9a, the cylindrical side wall portion 9b continuously formed on the upper portion of the bottom plate portion 9a, and the upper end portion of the side wall portion 9b. And a flange-shaped base portion 9c formed on the surface. The portions constituting the bottom plate portion 9a and the side wall portion 9b are made of transparent quartz so as not to block the light from the heat source 7, and the base portion 9c constituting the outer peripheral portion is made of an opaque quartz plate thicker than the bottom plate portion 9a.
The lower half of the lower dome 9 has the same structure as a conventionally known general vapor phase growth apparatus and is not important in the present invention, and therefore is not illustrated (the omitted parts are not disclosed in Japanese Patent Laid-Open No. 2003-2003). 133397, JP-A 2004-63779, JP-A 2003-124287, etc.).
The lower dome 9 can be attached to and detached from the base ring 10, and the maintenance work in the furnace can be performed by removing the lower dome 9 from the base ring 10 during maintenance of the lower reactor 5.

The base ring 10 is made of an annular member made of stainless steel, and the inner peripheral surface forms a straight hole having a circular shape when the base ring 10 is viewed from above. A circular seat surface is formed in a concave shape so that the base portion 8b of the upper dome 8 is fitted on the upper surface of the base ring 10, and a concave shape is formed on the lower surface so that the base portion 9c of the lower dome 9 is fitted. A circular seating surface is formed. An annular groove for inserting the O-ring 11 is provided in the upper seat surface, and an annular groove for inserting the O-ring 12 is provided in the lower seat surface.
The upper dome 8 is placed in a state where the O-ring 11 is sandwiched on the seating surface on the upper surface of the base ring. On the other hand, the lower dome 9 is fitted with the O-ring 12 sandwiched between the seating surface on the lower surface of the base ring. Although not shown, the outer periphery of the annular base ring 10 is further fitted to a bracket (not shown).

FIG. 2 is a perspective view schematically showing the base ring 10. As shown in FIG. 2, a gas inlet that penetrates in a horizontal direction from the outer wall surface of the base ring 10 to the inner peripheral wall of the base ring 10 is provided on the wall surface on the left side of the base ring 10 (matching the left side in FIG. 10a is formed. The gas inflow port 10a has a long hole shape whose opening cross section is long in the lateral direction, and two gas inlets 10a are formed. The two gas inlets 10a are adjacent to each other on the left and right and run in parallel with an interval of several mm to several cm.
On the other hand, a gas discharge port 10b penetrating in the horizontal direction from the inner peripheral wall surface of the base ring 10 to the outer wall of the base ring 10 is formed on the wall surface on the right side of the base ring 10 (corresponding to the right side of FIG. 1). ing. The gas discharge port 10b has a long hole shape whose opening cross section is long in the horizontal direction, and two gas discharge ports 10b are formed in the same manner as the gas inlet port 10a. The two gas discharge ports 10b are adjacent to each other on the left and right sides and are running in parallel with an interval of several mm to several cm. The gas discharge port 10b is formed on the inner peripheral wall surface facing the gas inlet 10a on the opposite side of the base ring 10.

As shown in FIG. 1, a quartz glass pipe 13 is inserted into the inner wall of the gas inlet 10a, and a quartz glass pipe 14 is inserted into the inner wall of the gas outlet 10b. The glass pipe 13 and the glass pipe 14 are fitted to the inner wall surfaces of the gas inlet 10a and the gas outlet 10b, respectively, with almost no gap.
The reaction gas (raw material gas and carrier gas) supplied from the gas inlet 10a flows through the glass pipe 13, flows through the upper reactor 3, passes through the glass pipe 14, and out of the chamber 2 through the gas outlet 10b. Discharged. By providing the glass pipe 13 and the glass pipe 14, it is possible to suppress the reaction gas from contacting the inner wall surfaces of the gas inlet 10a and the gas outlet 10b.

A wafer carry-in / out entrance 10c is formed on the front wall surface of the base ring 10 shown in FIG. The wafer loading / unloading port 10 c has a long hole shape with a long opening cross section in the horizontal direction, and the horizontal width of the opening is larger than the diameter of the wafer W. The wafer W is carried into the upper reaction furnace 3 through the wafer carry-in / out entrance 10c, and the wafer W after the epitaxial layer growth process is carried out of the upper reaction furnace 3 through the wafer carry-in / out entrance 10c. Loading and unloading of the wafer W is performed by a known transfer hand.
In addition, what is necessary is just to employ | adopt an appropriate dimension for the opening shape of the gas inflow port 10a, the gas exhaust port 10b, and the wafer carry-in / out port 10c mentioned above, a magnitude | size, and an arrangement position in consideration of the magnitude | size of the wafer W etc.

As shown in FIG. 1, a chamber shield 15 is provided inside the base ring 10. The chamber shield 15 is a quartz member having a generally cylindrical shape, and is formed by connecting a large-diameter cylinder and a small-diameter cylinder so that the longitudinal cross-sectional shape is a crank shape.
FIG. 4 is an enlarged view showing the vicinity of the gas outlet 10b of FIG. The chamber shield 15 is formed in a shape in which the outer peripheral surface is disposed along the inner wall of the base ring 10 and the inner wall surface of the base portion 9 c of the lower dome 9.

More specifically, the expansion dimension of the base ring 10 in the high temperature region is calculated from the temperature during the wafer reaction process of the base ring 10 exposed in the reaction furnace and the thermal expansion coefficient of stainless steel. Further, the expansion dimension of the chamber shield 15 in the high temperature region is calculated from the temperature during the reaction process of the wafer and the thermal expansion coefficient of quartz. Then, the dimension of the outer periphery of the chamber shield 15 is formed such that the outer peripheral surface of the chamber shield 15 contacts the inner wall of the base ring 10 due to thermal expansion during the wafer reaction process.
For example, considering the expansion dimensions of both, the outer dimension of the chamber shield 15 is processed with a dimension reduced by, for example, 0.3 mm from the inner dimension of the base ring 10 made of stainless steel. As a result, the chamber shield 15 can be substantially kept in close contact with the base ring 10 even in a high temperature region during the reaction processing of the wafer W, and the apparatus can be operated without the chamber shield 15 being broken.

In FIG. 4, the outer surface of the chamber shield 15 is disposed along the inner wall of the base ring 10 and the inner wall surface of the base portion 9 c of the lower dome 9, but the lower end of the chamber shield 15 extends to the side wall portion 9 b of the lower dome 9. It may extend.
The chamber shield 15 is merely mounted on the inner wall surface of the base portion 9c of the lower dome 9, and can be removed during maintenance. The quartz constituting the chamber shield 15 may be either transparent quartz or opaque quartz, or the chamber shield 15 may be formed of Si or SiC.

3A is a plan view of the chamber shield 15 as viewed from above, and FIG. 3B is a side view of the chamber shield 15 as viewed from the right direction in FIG. As shown in FIG. 3, a gas inflow opening 15 a and a gas exhaust opening 15 b are formed at positions corresponding to the gas inlet 10 a and the gas outlet 10 b of the base ring 10. The opening shapes of the gas inflow opening 15a and the gas discharge opening 15b are the same as the opening shapes of the gas inlet 10a and the gas outlet 10b.
Further, a wafer carry-in / out opening 15 c is formed at a position corresponding to the wafer carry-in / out port 10 c of the base ring 10. The opening shape of the wafer carry-in / out opening 15c is the same as the opening shape of the wafer carry-in / out opening 10c.

  According to the present embodiment, the chamber shield 15 is provided along the inner wall surface of the base portion 9 c of the lower dome 9 from the inner wall surface of the base ring 10, thereby suppressing the source gas from contacting the inner wall surface of the base ring 10. can do. Further, by providing the chamber shield 15, it is possible to suppress the accumulation of side reaction products on the inner wall surface of the base ring 10.

As shown in FIG. 1, an upper liner 16 is provided inside the base ring 10 near the upper dome 8, and a lower liner 17 is provided inside the base ring 10 near the lower dome 9.
The lower liner 17 is made of an annular opaque quartz, and is placed on the base portion 9 c of the lower dome 9 while being fitted to the inner periphery of the base ring 10.
The upper liner 16 is made of an annular opaque quartz and is placed on the lower liner 17 in a state of being fitted to the inner periphery of the base ring 10. The outer diameters of the upper liner 16 and the lower liner 17 are dimensions that just fit the inner periphery of the chamber shield 15.

As shown in FIG. 1, in the state where the upper liner 16 and the lower liner 17 are combined vertically, the gas inflow passage 18 and the gas exhaust passage are located at positions corresponding to the gas inflow port 10a and the gas exhaust port 10b of the base ring 10. A passage 19 is formed.
The shape of the opening on the side in contact with the base ring 10 of the gas inflow passage 18 is the same as the shape of the opening of the gas inlet 10a. On the other hand, the shape of the opening on the side in contact with the base ring 10 of the gas discharge passage 19 is the same as the shape of the opening of the gas discharge port 10b.
Furthermore, the longitudinal cross-sectional shape of the gas flow path formed by the gas inflow passage 18 and the gas exhaust passage 19 is bent in a crank shape, and the flow path in a cross-sectionally bent state is formed between the inside of the upper reactor 3 and the outside of the chamber 2. To communicate with each other.

The gas inflow passage 18 is a flow path for guiding the reaction gas (raw material gas and carrier gas) supplied from the gas inlet 10 a into the upper reaction furnace 3, and the reaction gas supplied from the gas inlet 10 a is the susceptor 4. Guide it so that it flows on the top surface.
On the other hand, the gas discharge passage 19 is a flow path for guiding the processed gas in the upper reaction furnace 3 to the gas discharge port 10b, and the reaction gas flowing on the upper surface of the susceptor 4 passes through the gas discharge port 10b to the outside of the chamber 2. To be discharged.
Further, an opening for wafer carry-in / out is formed at a position corresponding to the wafer carry-in / out port 10 c of the base ring 10.

  Further, a purge gas discharge hole 17a is formed in the lower liner 17, and the purge gas filled in the lower reactor 5 is discharged from the gas discharge port 10b through the purge gas discharge hole 17a.

By arranging the chamber shield 15, the space volume of the lower reaction furnace 5 becomes narrower than before. Since the lower reaction furnace 5 and the upper reaction furnace 3 are designed to have a balanced structure with respect to the amount of gas supplied, only the space volume of the lower reaction furnace 5 becomes narrow, resulting in a problem in wafer quality. There is.
Therefore, a concave portion 17b for volume adjustment is formed in the lower liner 17, and the space volume corresponding to the narrowed portion of the lower reactor 5 is added. The recessed portion 17b is a recessed depressed portion formed on the inner peripheral wall surface of the lower liner 17, and may be provided in a groove shape on the entire inner peripheral wall surface of the lower liner 17, or a spot portion of the inner peripheral wall surface. You may provide in a part.
By providing the recessed portion 17b, the lower reaction furnace 5 can maintain a space volume equivalent to that of a conventional apparatus that does not include the chamber shield 15.

Further, when the space volume of the upper reactor 3 becomes narrower than before due to the arrangement of the chamber shield 15, the upper reactor 3 is formed by forming a convex portion for volume adjustment in the lower liner 17. The lower reactor 5 is also narrowed by the narrowed space volume.
That is, it is only necessary to provide the lower liner 17 with an adjustment unit for correcting the difference in the change in the space volume generated between the upper reaction furnace 3 and the lower reaction furnace 5 by providing the chamber shield 15. The adjustment part may be concave or convex. The adjustment unit can be provided on the upper liner 16 and may be provided on at least one of the upper liner 16 and the lower liner 17. However, since the gas flow flowing on the wafer W may change when it is provided on the upper liner 16, it is desirable to provide the adjusting portion on the lower liner 17.

  In the present invention, the upper liner 16 and the lower liner 17 are divided into two parts, but the upper liner 16 and the lower liner 17 may be integrally formed by one member.

  A susceptor 4 that horizontally supports only one wafer W is disposed in the chamber 2. The susceptor 4 has a disk shape when viewed from above, and its diameter is larger than that of the wafer W. The susceptor 4 is disposed so that the plate surface is horizontal, and a circular recess for storing a wafer in which the wafer W is stored is provided on the upper surface of the susceptor 4.

An annular plate-shaped susceptor ring 20 is provided around the susceptor 4. The susceptor ring 20 is placed on a flange portion provided on the lower liner 17. The susceptor 4 is accommodated in the inner periphery of the susceptor ring 20, and the upper surface of the susceptor 4 and the upper surface of the susceptor ring 20 are arranged in substantially the same plane.
The internal space of the chamber 2 is divided into an upper reaction furnace 3 and a lower reaction furnace 5 by the susceptor 4 and the susceptor ring 20.

The susceptor 4 rotates around the susceptor support shaft 21 in the plane parallel to the plate surface of the wafer W during the epitaxial layer growth processing operation. The center of the susceptor housing recess provided in the susceptor 4 coincides with the center of rotation of the susceptor 4.
As a result, the supplied reaction gas (raw material gas and carrier gas) uniformly contacts the upper surface of the wafer W, and an epitaxial layer having a uniform thickness is formed on the wafer W.
The rotation to the susceptor support shaft 21 is given by a rotation drive mechanism (not shown).

In this embodiment, the susceptor 4 is a carbon C base material coated with a silicon carbide SiC film, and serves as a soaking plate for keeping the temperature of the entire wafer W uniform when the wafer W is heated. Fulfill. Therefore, the susceptor 4 has a thickness several times that of the wafer W, that is, a heat capacity several times that of the wafer W.
On the other hand, the susceptor ring 20 is also a carbon C base material coated with silicon carbide SiC in the present embodiment, and serves as a soaking plate for keeping the temperature at the outer periphery of the susceptor 4 uniform. Fulfill.

  In order to transport the wafer W onto the susceptor 4, a lift mechanism for moving the wafer W up and down relative to the susceptor 4 is provided. The lift mechanism has a plurality of lift pins 22 extending through the susceptor 4, and the wafer W is moved up and down by placing the wafer W on the upper ends of the lift pins 22 and moving the lift pins 22 up and down. it can. Although only two lift pins 22 are shown in FIG. 1, only the illustration is omitted, and in the present embodiment, three lift pins 22 are provided. The lift pins 22 are not limited to three, and may be three or more.

The susceptor 4 is provided with three through holes 4a (only two are shown in FIG. 1) distributed at an equal angle (120 °) with respect to the center of the susceptor 4. The upper part of each through hole 4a opens upward in the recess for storing wafers. Wafer support lift pins 22 are inserted into the three through holes 4a.
The lift pin 22 can freely move in the vertical direction in the through hole 4a of the susceptor 4. The diameter of the through hole 4 a is slightly larger than the diameter of the lift pin 22, and is formed in such a size that the lift pin 22 does not rattle when the lift pin 22 moves up and down with respect to the susceptor 4. The lift pins 22 are made of quartz, silicon Si, silicon carbide SiC, quartz coated with silicon Si or silicon carbide SiC, and the like.

The upper end portion of the lift pin 22 has a head having a diameter larger than that of the through hole of the susceptor 4. The lift pin 22 is suspended from the susceptor 4 through the through hole 4a when the head is locked to the enlarged opening of the through hole 4a. The shape of the lower surface of the head conforms to the shape of the inner wall surface of the enlarged opening of the through hole 4a, and comes into surface contact with the inner wall surface of the enlarged opening. As a result, the head becomes an excellent seal with respect to the through hole 4a, whereby the reaction gas leaks through the gap between the lift pin 22 and the through hole 4a to the lower side of the susceptor 4 and the lower side of the wafer W is burnt. Is prevented.
Further, by filling the lower reaction furnace 5 with hydrogen H ₂ as a purge gas, the raw material gas is prevented from leaking from the upper reaction furnace 3 to the lower reaction furnace 5.

  The head of the lift pin 22 has a convex shape whose apex portion forms an obtuse angle, and makes point contact with the back surface of the wafer W. Thereby, the generation | occurrence | production of the damage | wound in the back surface of the wafer W is suppressed to the minimum. Further, by forming the apex portion (contact portion) in a smooth parabola or arc shape, it is possible to further suppress the occurrence of scratches on the back surface of the wafer.

Three elevating arms 24 (only two are shown in FIG. 1) are attached to the upper end of a cylindrical elevating shaft 23 arranged concentrically with the susceptor supporting shaft 21 with respect to the susceptor supporting shaft 21. It is dispersed and fixed at an angle (120 °). The upper end of the elevating arm 24 has a pin support surface 24 a for supporting the lift pin 22. The pin support surface 24 a has a structure separated from the lift pin 22.
The elevating shaft 23 moves up and down independently of the susceptor support shaft 21 by an elevating mechanism (not shown) such as a hydraulic cylinder.

When the lifting arm 24 is raised or the susceptor 4 is lowered, the pin support surface 24 a of the lifting arm 24 supports the lower end of the lift pin 22 and lifts the lift pin 22 relative to the susceptor 4. At that time, the heads of the lift pins 22 support the back surface of the wafer W and lift the wafer W. As a result, the wafer W is lifted from the recess for storing the wafer, and a transfer hand can be arranged under the wafer W.
A transfer hand is inserted into the chamber through the wafer carry-in / out port 10c, and the lift arm 24 is lowered or the hand is lifted while the transfer hand is placed under the wafer W, whereby the transfer hand is moved from the susceptor 4 to the transfer hand. Can be handed over to. Further, by performing an operation reverse to the above, the wafer W placed on the transfer hand and carried into the chamber 2 can be transferred onto the susceptor 4.

  By such a lift mechanism, the wafer W placed on the transfer hand and carried into the chamber 2 is transferred onto the susceptor 4, or vice versa, the wafer W is transferred from the susceptor 4 to the transfer hand. It becomes possible to do.

A susceptor support 25a that horizontally supports the susceptor 4 is in contact with the lower surface of the susceptor 4 to support the susceptor 4 from below. Three support arms 25 (only two are shown in FIG. 1) are provided on the top of the susceptor support shaft 21, and each has a susceptor support 25a at the tip. Each support arm 25 is arranged radially from the center of the susceptor support shaft 21 so that each support arm 25 forms an angle of 120 ° when viewed from above.
In order to prevent the lift pin 22 from rattling and to lift the lift pin 22 vertically, the support arm 25 is provided with a straight hole-shaped guide hole 25b penetrating in the vertical direction, and the middle of the lift pin 22 is inserted through the guide hole 25b. is doing. The lift pin 22 can be stably moved in a substantially vertical direction by inserting the through hole 4a and the guide hole 25b of the susceptor 4.

When the wafer W is heat-treated in the chamber 2, the elevating arm 24 is disposed at a lowered position. The lift pins 22 are suspended from the through holes of the susceptor 4 by their own weight. The rotational drive from the susceptor support shaft 21 is transmitted to the support arm 25, and the susceptor 4 rotates.
At this time, the lift pin 22 rotates independently of the lifting arm 24 while being suspended from the susceptor 4. Since the lift pin 22 is supported by the guide hole 25b at the middle, the tilt due to the centrifugal force during rotation is prevented.

The susceptor 4 is placed on the susceptor support 25a so that the center of the susceptor 4 and the axis of the susceptor support shaft 21 coincide with each other, and the susceptor 4 rotates stably without being shaken by the rotation of the susceptor support shaft 21. . The rotation to the susceptor support shaft 21 is given by a rotation driving motor (not shown).
The susceptor support shaft 21, the support arm 25, and the susceptor support 25a are made of high-transparency, high-purity transparent quartz so as not to block light from the lower heat source 7. Preferably, the lifting arm 24 is also made of transparent quartz with high translucency and high purity.

In order to grow an epitaxial layer, it is necessary to flow a reaction gas (a raw material gas and a carrier gas) over the wafer W and to heat the wafer W supported on the susceptor 4 to a high temperature of about 1000 to 1200 ° C. Therefore, heat sources 6 and 7 for heating the upper reaction furnace 3 are provided above and below the chamber 2. An infrared lamp or a far-infrared lamp can be used as the upper and lower heat sources 6 and 7, and the susceptor 4 and the wafer W are heated from the upper and lower sides of the chamber 2. In the present embodiment, halogen lamps are used as the upper and lower heat sources 6 and 7.
The upper and lower heat sources 6 and 7 heat the wafer W and the susceptor 4 through the upper dome 8 and the lower dome 9 by radiant heat, and set the wafer W to a predetermined temperature suitable for the reaction process.

The source gas and carrier gas flow into the upper reaction furnace 3 from the gas inlet 10a shown in FIG. 1, and the reacted gas and carrier gas are discharged from the other gas outlet 10b. Further, hydrogen H ₂ is supplied as a purge gas from below the chamber 2, and the purge gas filled in the lower reaction furnace 5 is discharged from the gas discharge port 10b through the purge gas discharge hole 17a.
Note that the structure for supplying the purge gas to the lower reactor 5 is the same as that of a conventionally known general vapor phase growth apparatus, and is not shown in the figure because it is not important in the present invention (omitted). (See JP 2004-637779 A).

As the source gas, chlorosilane-based gas such as trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ is generally used. These gases are introduced into the chamber ₂ together with hydrogen H _{2 as} a carrier gas, and an epitaxial layer is generated on the wafer surface by a thermal CVD reaction.

Next, the manufacturing method of the epitaxial wafer W by the vapor phase growth apparatus 1 mentioned above is demonstrated.
First, the upper and lower heat sources 6 and 7 are operated to raise the temperature in the chamber 2 to a temperature suitable for the growth of the epitaxial layer. The growth temperature of the epitaxial layer is preferably about 1000 to 1200 ° C., and is controlled so as to maintain the above temperature range while detecting the temperature of the susceptor 4 in the upper reaction furnace 3 with a thermosensor or the like.
Thereafter, hydrogen H ₂ is supplied as a carrier gas from the gas inlet 10a, and the upper reaction furnace 3 is filled with the carrier gas.

Further, hydrogen H ₂ is supplied as a purge gas from below the chamber 2, and the inside of the lower reaction furnace 5 is filled with the purge gas. The purge gas filled in the lower reaction furnace 5 is discharged from the gas discharge port 10b through the purge gas discharge hole 17a provided in the lower liner 17.
Since the upper reactor 3 has the gas discharge port 10b on the opposite side of the gas inlet 10a, the carrier gas always flows from the gas inlet 10a toward the gas discharge port 10b. In general, hydrogen H ₂ is often used as the carrier gas. In the present embodiment, a slight amount of diborane B ₂ H ₆ added as an impurity to the hydrogen H ₂ is used. The carrier gas has a flow rate of hydrogen H ₂ of about 60 l / min, while a flow rate of diborane B ₂ H ₆ is about several cc / min. This carrier gas is usually supplied into the upper reaction furnace 3 at room temperature (room temperature).

Next, when the inside of the upper reaction furnace 3 is sufficiently heated and the carrier gas is filled, the wafer W is loaded into the upper reaction furnace 3 this time. In the present embodiment, the wafer W has a diameter of about 200 mm and a thickness of about 0.75 mm. The wafer W is placed on a quartz transport hand, the hand is inserted into the chamber 2, and the wafer W is stored in the wafer storage recess of the susceptor 4. When the susceptor 4 is rotated and the rotation is stabilized, the source gas is supplied into the chamber 2 from the gas inlet 10a.
As the source gas, trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ is generally used. For example, in an example using trichlorosilane SiHCl ₃ , a raw material gas consisting of 15 to 25 percent of trichlorosilane SiHCl ₃ and the balance of hydrogen H ₂ is used, and a flow rate of about 10 to 15 l / min is mixed into the carrier gas and supplied. Is preferred.

A reactive gas flows on the surface of the wafer W, and an epitaxial layer begins to grow on the wafer surface. Since the wafer W is rotated in a horizontal plane while being accommodated in the susceptor 4, an epitaxial layer having a substantially uniform thickness grows on the surface of the wafer W.
When the epitaxial layer having a desired thickness is grown, the supply of the reaction gas is stopped. Then, the processed wafer W is unloaded from the chamber 2 by using a transfer hand.

A chlorosilane-based gas such as trichlorosilane SiHCl ₃ or dichlorosilane SiH ₂ Cl ₂ used as a raw material gas causes a chemical reaction in the upper reaction furnace 3, and a Si _x -H _y -Cl _z compound is produced as a side reaction product. Generated. In particular, the Si _x —H _y —Cl _z compound tends to accumulate in the vicinity of the gas inflow passage 18 and the gas exhaust passage 19 formed by the upper liner 16 and the lower liner 17.
If the accumulated side reaction product is peeled off during the processing of the wafer W, it causes wafer contamination. Therefore, after processing a specific number of wafers W or after a specific time has elapsed, the upper dome 8 is removed and the upper side is removed. Deposits in the reaction furnace 3 are removed. Side reaction products deposited on the upper liner 16 and the lower liner 17 are removed by hydrofluoric acid cleaning.

FIG. 4 is an enlarged view showing the vicinity of the gas outlet 10b as in FIG. As shown in FIG. 4, in the present embodiment, a chamber shield 15 is provided along at least the inner wall surface of the base ring 10. By cleaning the upper liner 16 and the lower liner 17 with hydrofluoric acid, the upper liner 16 and the lower liner 17 are thinned, and as shown in FIG. 4, between the upper liner 16 and the base ring 10 and between the lower liner 17 and the base ring 10. A gap 33 may be formed between them.
According to the present invention, since the chamber shield 15 is provided along the inner wall surface of the base ring 10, even if the gap 33 is formed, the source gas is suppressed from contacting the inner wall surface of the base ring 10. As a result, it is possible to reduce corrosion of the base ring 10 during the epitaxial layer generation process.

FIG. 5 is a comparative graph obtained by measuring the epitaxial wafer quality after wafer processing in the conventional vapor phase growth apparatus shown in FIG. 8 and the vapor phase growth apparatus of the present invention shown in FIG. The vertical axis indicates the quality of the wafer after the epitaxial layer is generated, and the horizontal axis indicates the number of processed wafers. In general, the higher the number of iron boron atoms in the epitaxial layer, the lower the quality of the wafer. If iron boron atoms exceeding a specified value are detected, the wafer cannot be shipped as a defective product.
When the base ring is severely corroded, iron boron atoms diffuse into the reactor and the number of iron boron atoms in the epitaxial layer increases. Therefore, it can be seen that the lower the wafer quality, the more severe the base ring is corroded.

In the graph, when the reactor was opened to the atmosphere for maintenance at the time indicated by the alternate long and short dash line, the wafer quality was temporarily abruptly bad in the conventional device, whereas in the device of the present invention, the wafer quality was There was no sudden deterioration. From this, it can be seen that according to the present invention, the corrosion of the base ring is reduced as compared with the conventional apparatus when the reactor is opened to the atmosphere.
In addition, when the reactor was opened to the atmosphere, many of the corroded gel-like stainless deposits (deposition) were generated near the gas outlet 10b of the base ring 10 in the conventional vapor phase growth apparatus. In the vapor phase growth apparatus of the invention, the occurrence of deposition was suppressed to a small extent.

According to the present invention, by providing the chamber shield 15 along at least the inner wall surface of the base ring 10, it is possible to suppress the source gas from contacting the inner wall surface of the base ring 10.
As a result, the corrosion of the base ring 10 during the epitaxial layer growth process can be reduced.

  Further, the upper liner 16 and the lower liner 17 are thinned by cleaning the hydrofluoric acid of the upper liner 16 and the lower liner 17, and as shown in FIG. Even if a gap 33 is formed between the two, the chamber shield 15 is provided along the inner wall surface of the base ring 10, so that the source gas is prevented from contacting the inner wall surface of the base ring 10.

Furthermore, by providing the chamber shield 15, the side reaction product is deposited on the chamber shield 15, so that the side reaction product can be prevented from being directly deposited on the inner wall surface of the base ring 10. If the Si _x —H _y —Cl _z compound produced as a side reaction product is not deposited on the inner wall surface of the base ring 10, even if the upper reactor 3 is opened to the atmosphere during maintenance, the Si _x − Corrosion of the base ring 10 due to hydrolysis of the H _y —Cl _z compound can be prevented.
As a result, since the frequency of maintenance work for removing the corroded gel-like stainless steel deposit (deposition) using a spatula such as a scraper is reduced, the yield of the product can be improved as compared with the prior art.

  In addition, by removing and replacing only the chamber shield 15, it is possible to save time and labor for disassembling, cleaning and replacing the reactor itself. Therefore, parts cost and maintenance cost can be reduced, and an inexpensive and high-quality silicon wafer can be provided.

  9 and 10 are longitudinal sectional views showing other embodiments of the present invention, and are enlarged views showing the vicinity of the gas discharge port 10b as in FIG. In the example shown in FIG. 9, the chamber shield 35 is made of a quartz member having a flange portion projecting inwardly at a cylindrical lower end portion. The longitudinal section of the chamber shield 35 is L-shaped, and the outer peripheral surface is disposed along the inner wall of the base ring 10 and the upper surface of the base portion 9 c of the lower dome 9.

On the other hand, in the example shown in FIG. 10, the chamber shield 45 is made of a cylindrical quartz member. The chamber shield 45 is provided such that its outer peripheral surface is along the inner wall of the base ring 10.
The same effects as those of the chamber shield 15 can be obtained by the chamber shields 35 and 45 shown in FIGS. Thus, in the present invention, the chamber shield may be provided so as to extend along at least the inner wall of the base ring 10.

Moreover, in the conventional vapor phase growth apparatus 31 shown using FIG. 8, the corrosion of the base ring 10 is particularly severe in the vicinity of the gas inlet 10a and the gas outlet. Therefore, a chamber shield may be partially provided only in the vicinity of the gas inlet 10a or in the vicinity of the gas outlet on the inner peripheral wall surface of the base ring 10.
In this case, the chamber shield may be provided only in one of the more corrosive portions near the gas inlet 10a or the gas outlet.

  That is, in the present invention, it is not necessary to provide a chamber shield on the entire inner peripheral surface of the base ring 10, and a configuration in which only a part is provided may be used. Even in this case, the metal corrosion of the portion covered with the chamber shield can be remarkably reduced.

  According to the present invention, the metal parts exposed in the reaction furnace are covered with a high-purity quartz glass plate produced in the same shape as the exposed metal parts surface shape, so that the conventional reactive gas can be contacted or sub-charged. Contact with the reaction product can be blocked.

  In the above embodiment, the single-wafer type vapor phase growth apparatus has been described. However, the present invention is naturally applicable to a batch type vapor phase growth apparatus that collectively processes a plurality of wafers. be able to.

  Further, the layer for vapor phase growth does not need to be an epitaxial layer, and the present invention can be applied to other vapor phase growth layers.

  In the above embodiment, a semiconductor wafer is described as an example of a workpiece. However, the workpiece is not limited to a semiconductor wafer but can be applied to a wafer (thin plate-like material) made of other materials. it can.

  The shape of the workpiece is not limited to a disk-shaped wafer, but can be applied to a square or polygonal wafer. Further, the present invention is not limited to a thin plate-like wafer, and can be applied to a workpiece having any shape.

  In the above embodiment, the base ring made of stainless steel has been described. However, the base ring need not be made of stainless steel, and may be made of other metals. In the case where other metals may become contaminants in the reaction furnace, the present invention is applied, and metal contamination can be reduced by covering the metal parts with quartz glass.

  In addition, the material for the chamber shield is not limited to quartz glass, and other materials can be used as long as they are materials that do not cause contamination of wafers or epitaxial layers as workpieces.

1 is a longitudinal sectional view schematically showing a vapor phase growth apparatus according to an embodiment of the present invention. It is a perspective view of the base ring used for the vapor phase growth apparatus concerning one embodiment of the present invention. FIG. 3A shows a chamber shield used in a vapor phase growth apparatus according to an embodiment of the present invention, FIG. 3A is a plan view of the chamber shield, and FIG. 3B is a side view of the chamber shield. It is an enlarged view which shows the longitudinal cross-section of the gas exhaust port vicinity in the vapor phase growth apparatus provided with the chamber shield which concerns on one embodiment of this invention. It is a comparison graph of the quality of the epitaxial wafer of the conventional vapor phase growth apparatus and the vapor phase growth apparatus of this invention. It is an enlarged view which shows the longitudinal cross-section of the gas exhaust port vicinity in the conventional vapor phase growth apparatus. It is an enlarged view which shows the longitudinal cross-section of the gas discharge port vicinity in the conventional vapor phase growth apparatus after wash | cleaning an upper liner and a lower liner with a hydrofluoric acid. It is a longitudinal cross-sectional view which shows the conventional vapor phase growth apparatus typically. It is an enlarged view which shows the longitudinal cross-section of the gas exhaust port vicinity in the vapor phase growth apparatus provided with the chamber shield which concerns on the other form of this invention. It is an enlarged view which shows the longitudinal cross-section of the gas exhaust port vicinity in the vapor phase growth apparatus provided with the chamber shield which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vapor growth apparatus 2 ... Chamber 3 ... Upper reactor 4 ... Susceptor 4a ... Through-hole 5 ... Lower chamber 6 ... Upper heat source 7 ... Lower heat source 8 ... Upper dome 8a ... Top plate part 8b ... Base part 9 ... Lower dome 9a ... Bottom plate part 9b ... Side wall part 9c ... Base part 10 ... Base ring 10a ... Gas inlet 10b ... Gas outlet 10c ... Wafer outlet / inlet 11 ... O ring 12 ... O ring 13 ... Glass pipe 14 ... Glass pipe 15 ... Chamber shield DESCRIPTION OF SYMBOLS 15a ... Gas inflow opening 15b ... Gas discharge opening 15c ... Wafer carry-in / out opening 16 ... Upper liner 17 ... Lower liner 17a ... Purge gas discharge hole 17b ... Recessed portion 18 ... Gas inflow passage 19 ... Gas discharge passage 20 ... Susceptor ring 21 ... Susceptor support shaft 22 ... Lift pin 23 ... Lifting shaft 24 ... Lifting shaft 24a ... pin support surface 25 ... support arm 25a ... susceptor support 25b ... guide hole 31 ... vapor phase growth apparatus 32 ... side reaction product 33 ... gap 35 ... chamber shield 45 ... chamber shield W ... wafer.

Claims (9)

A support for supporting a workpiece for forming a vapor phase growth layer on at least a part of the surface;
A reactor formed by surrounding the periphery of the support by a plurality of components including metal parts made of metal that can be a contaminant to the vapor phase growth layer or the workpiece;
In a vapor phase growth apparatus comprising:
At least a part of the inner wall surface of the metal part constituting a part of the inner wall surface of the reaction furnace is covered with a substance that does not become a contaminant for the vapor phase growth layer or the workpiece. Vapor growth equipment. A wafer support for supporting a wafer for vapor-phase growth of an epitaxial layer on the upper surface;
A reaction furnace formed by surrounding the periphery of the wafer support with a plurality of components including metal parts;
In a vapor phase growth apparatus comprising:
A vapor phase growth apparatus characterized in that at least a part of the inner wall surface of the metal part constituting a part of the inner wall surface of the reactor is covered with a quartz glass plate. A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
In a vapor phase growth apparatus comprising:
A vapor phase growth apparatus characterized in that at least a part of an inner peripheral wall surface of the base ring constituting a part of an inner wall surface of the reaction furnace is covered with a substance that does not become a contaminant to the epitaxial layer or the wafer. .   4. The vapor phase growth apparatus according to claim 1, wherein the substance that does not become a contaminant is quartz. The metal part has at least one of a gas inlet for supplying gas into the reactor or a gas outlet for discharging gas in the reactor,
3. The air according to claim 1, wherein at least a part of the inner wall surface of the metal part is an inner wall surface adjacent to at least one of the gas inlet or the gas outlet. Phase growth equipment. The metal part has at least one of a gas inlet for supplying gas into the reactor or a gas outlet for discharging gas in the reactor,
The vapor phase growth apparatus according to claim 1 or 2, wherein an inner wall surface of at least one of the gas inlet or the gas outlet is covered with quartz. A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
In a vapor phase growth apparatus comprising:
A vapor phase growth apparatus characterized in that an inner peripheral wall surface of the base ring constituting a part of an inner wall surface of the reactor is covered with a chamber shield made of a detachable quartz glass plate. From the temperature of the reactor and the thermal expansion coefficient of the material constituting the base ring, obtain the expansion dimension of the base ring in a high temperature range,
From the temperature of the reactor and the coefficient of thermal expansion of the material constituting the chamber shield, obtain the expansion dimension of the chamber shield in a high temperature range,
In consideration of the expansion dimensions of both, the chamber shield is formed so that the outer peripheral surface of the chamber shield does not come into contact with the inner peripheral wall surface of the base ring due to thermal expansion during the reaction process of the wafer. The vapor phase growth apparatus according to claim 7. A susceptor which is placed in a reaction furnace and on which a wafer for vapor-phase growth of an epitaxial layer is placed on the upper surface;
An annular metal base ring;
An upper dome and a lower dome made of quartz for constituting the reactor by sandwiching the base ring from above and below,
An upper liner and a lower liner disposed in the reactor;
In a vapor phase growth apparatus comprising:
By covering the inner peripheral wall surface of the base ring constituting a part of the inner wall surface of the reactor with a chamber shield made of a quartz glass plate, the upper reactor and the reactor of the reactor above the susceptor of the reactor In order to correct the difference in the furnace volume change that occurs between the lower reactor and the lower reactor below the susceptor, an adjustment unit for adjusting the furnace volume is provided in at least one of the upper liner and the lower liner. A vapor phase growth apparatus characterized by that.

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