JP4655801B2 - Epitaxial growth apparatus and epitaxial wafer manufacturing method - Google Patents

Description

  The present invention relates to a single-wafer epitaxial growth apparatus using a vapor phase growth method, and more particularly to an epitaxial growth apparatus and an epitaxial wafer manufacturing method capable of improving the uniformity of film thickness distribution of an epitaxial layer to be grown.

In the field of manufacturing semiconductor wafers such as silicon wafers, so-called epitaxial wafers in which a silicon epitaxial layer is formed on the surface of a substrate are known. An epitaxial wafer can form a single crystal silicon layer (epitaxial layer, epitaxial film) having an arbitrary thickness and resistivity on the wafer, and can also solve the problem of grow-in defects that hinder device manufacturing. Therefore, in recent years, the range of use has expanded.
Vapor phase growth is widely used for epitaxial growth of silicon wafers. At that time, silane-based gases (SiH4, SiHC13, SiH2C12, SiC14) are widely used as source gases, and H2 is widely used as a carrier gas.

  Incidentally, in recent years, there has been a strong demand for higher integration of semiconductor devices, and in the manufacturing process, pattern miniaturization is required. Along with this, improvement in quality is also required for epitaxial wafers, and in epitaxial wafers, it is required to make the thickness of the epitaxial film uniform in order to ensure the flatness of the wafer surface. In particular, from the desire to improve the yield, that is, the desire to manufacture a large number of devices from a single wafer, the film thickness is uniform over a wide range of wafers, in other words, from the outer periphery of the wafer to a few millimeters. There is a need to improve and maintain quality, including sexuality.

  However, since the epitaxial growth is usually performed under a supply-controlled condition by heating the wafer to a high temperature, the thickness of the formed epitaxial layer is easily affected by the flow velocity of the gas flowing over the wafer. For this reason, in the conventional epitaxial growth apparatus, there has been a case where the uniformity of the film thickness cannot be sufficiently ensured due to the nonuniformity of the gas flow flowing through the upper space of the wafer.

As a method for making the gas flow uniform, a method of supplying gas to a chamber through a rectifying member using a porous baffle is conventionally known.
Also, there is a method of supplying gas to the upper space of the wafer at a uniform speed and concentration by passing the gas into the chamber through a rectifying member having an independent collision wall and an inclined joining member. It has been proposed (for example, see Patent Document 1).
JP 2005-72118 A

As shown in FIG. 12, there is also known a method of making the gas distribution uniform by a diffusion effect using a collision wall 121 curved along the furnace shape.
In FIG. 12, a stepped stepped portion 120 is provided at the connecting portion of the chamber side wall member 12 constituting the chamber 10 with the rectifying member 23, and the vertical surface 121 of the stepped portion 120 is configured as a collision wall. . In such a configuration, the reaction gas supplied through the rectifying member 23 flows over the wafer W in the chamber 10 while being diffused by the collision wall 121.

However, even if an epitaxial growth apparatus in which the gas flow is made uniform by such a conventional method is used, the uniformity of the thickness of the grown epitaxial film is not sufficient, and it is more uniform with higher accuracy. It is desired to form a thick epitaxial layer.
In particular, high integration of semiconductor devices in recent years is remarkable, and in the device manufacturing process, fine processing is performed in consideration of, for example, the depth of focus of the exposure apparatus in the photolithography process. For this purpose, it is required that the silicon wafer used as the device material has a high flatness, but if the epitaxial layer thickness is not sufficient, the processing accuracy from slicing to polishing will be improved and the flatness of the underlying wafer will be increased. However, the flatness of the wafer surface deteriorates as a result. As a result, it becomes impossible to perform fine processing on the wafer with high accuracy and high yield, which adversely affects device performance and device productivity.

Specifically, for example, in the conventional method of supplying gas to the chamber by a rectifying member using a perforated baffle, there is a problem that the gas flow rate is increased or decreased under the influence of baffle holes.
Further, in the method of making the gas distribution uniform by the diffusion effect by causing the gas to collide with the curved wall surface 121 exemplified with reference to FIG. 12, the stepped portion side wall 122 of the curved portion 121 is formed as shown in FIG. Since the gas is drawn in the direction of the center of the wafer so as to guide the gas onto the wafer, the flow rate of the gas flowing near the center of the wafer increases and the growth rate increases. In the vicinity of the inner wall of the furnace, there is a problem that the gas flow rate is lowered and the epitaxial growth rate is lowered.

  The present invention has been made in view of such problems, and its purpose is to grow by making the flow path, flow rate, flow velocity, and the like of the gas flow flowing on the wafer uniform at each position on the wafer. An object of the present invention is to provide an epitaxial growth apparatus and an epitaxial wafer manufacturing method capable of improving the uniformity of the film thickness distribution of the epitaxial film.

  In order to solve the above-mentioned problems, the inventor of the present application has intensively studied the flow path, flow rate, flow rate, and the like of the gas that is supplied into the chamber of the epitaxial growth apparatus and flows on the wafer. As a result, the flow rate of the reaction gas supplied to the peripheral edge of the wafer changes depending on the shape of the end of the supply opening for supplying the reaction gas to the chamber, which affects the growth rate of epitaxial growth. It was also found that the end shape of the air supply opening suitable for making the flow rate of the reaction gas on the wafer uniform can be obtained.

Accordingly, an epitaxial growth apparatus according to the present invention is provided at a connection portion between a chamber that accommodates a wafer, an air supply member that supplies a reaction gas to the chamber, and the air supply member of the chamber. An air supply connection for supplying the reaction gas to be supplied to the upper side of the wafer through a passage opening formed with the radial direction of the wafer housed in the chamber as a longitudinal direction, A side wall surface for forming the side wall of the passage opening at both ends in the longitudinal direction of the passage opening of the air connection and guiding the reaction gas passing near the end toward the peripheral edge of the wafer. sidewall member having is arranged, the wall member is such that said width of the passage openings of the reaction gas becomes wider with increasing vertically upwards, the side wall surface in the vertical direction It is formed obliquely.

  Preferably, the air supply connection portion is a wall surface protruding in a curved manner with respect to a direction in which the reaction gas is supplied from both end portions to the center portion in the longitudinal direction of the passage opening portion. It has a curved collision wall surface that diffuses the reaction gas when the gas collides.

  Preferably, the side wall surface of the side wall member has a direction in which the side wall surface extends in the direction of the wafer accommodated in the chamber with respect to the flow direction of the reaction gas supplied from the air supply member. And formed so as to be shallower than the direction from the end of the passage opening to the center of the wafer disposed in the chamber.

Preferably, the side wall surface of the side wall member is inclined in a range of greater than 0 ° and not more than 60 ° with respect to the vertical surface.

  Preferably, the side wall member is a detachable member.

  Moreover, the epitaxial wafer manufacturing method which concerns on this invention manufactures an epitaxial wafer using the epitaxial growth apparatus in any one of the above-mentioned.

  According to the present invention, the uniformity of the film thickness distribution of the epitaxial film to be grown is improved by making the flow path, flow rate, flow velocity, and the like of the gas flow flowing on the wafer uniform at each position on the wafer. It is possible to provide an epitaxial growth apparatus and an epitaxial wafer manufacturing method capable of achieving the above.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a vertical sectional view showing a schematic configuration of an epitaxial growth apparatus according to the present invention, and FIG. 2 is a planar sectional view taken along line AA ′ of FIG.

As shown in FIG. 1, the epitaxial growth apparatus 1 includes an upper chamber member 11, a chamber side wall member 12, and a lower chamber member 13, and a space surrounded by these constitutes an epitaxial film forming chamber. The upper chamber member 11, the chamber sidewall member 12, and the lower chamber member 13 are each made of a transparent material such as quartz.
A susceptor 26 on which the wafer W is placed is disposed inside the epitaxial film forming chamber. The susceptor 26 is formed of, for example, a material obtained by coating the surface of a carbon base material with a SiC film, and is configured to support the entire back surface of the wafer W. During the epitaxial growth process, the susceptor 26 on which the wafer W is placed is rotated at a constant rotational speed by the susceptor support 30.

The epitaxial film forming chamber is divided into an epitaxial film forming chamber upper portion 14 and an epitaxial film forming chamber lower portion 15 with the susceptor 26 and the wafer W arranged at the processing position as a boundary during the epitaxial growth processing.
Around the susceptor 26, a preheating ring 25 for heating a room temperature gas introduced into the epitaxial film forming chamber is disposed.
A plurality of heating lamps 29 (for example, infrared lamps) are disposed above and below the chamber 10, respectively.

In addition, as shown in FIG. 2, the epitaxial growth apparatus 1 includes piping 33, 34, 35, flow controllers 31 and 32, an inlet member 21 (see FIG. 1), a baffle 22, and a rectifying member 23, The exhaust system includes an exhaust side rectifying member 27 and an exhaust port 28 (see FIG. 1).
Silane gases (SiH 4, SiC 12 H 2, SiHC 13, SiC 14) and carrier gas H 2 (hereinafter simply referred to as gases) serving as source gases are introduced into the epitaxial growth apparatus 1 through a pipe 33, and are supplied to the pipes 34 and 35. After branching, the gas flow rate is adjusted by the flow rate adjusters 31 and 32. Thereafter, the gas passes through the inlet member 21 (see FIG. 1), the baffle 22, and the rectifying member 23, and then passes through the flow path 120 (air supply side step portion 120 described later) formed in the chamber side wall member 12 to form an epitaxial film. Guided to the upper room 14.

As shown in FIG. 2, partition plates 24 and 125 are provided on the air supply side step portion 120 of the rectifying member 23 and the chamber side wall member 12. These partition plates 24 and 125 are members that partition the gas flow path in the rectifying member 23 and the flow path (stepped portion) 120 formed in the chamber side wall member 12 with the gas flow path direction as the extension surface.
The gas introduced into the upper part 14 of the epitaxial film forming chamber passes over the wafer W. Thereby, the source gas is used for forming an epitaxial film on the wafer W. The gas that has passed over the wafer W is discharged from the epitaxial growth apparatus 1 through the exhaust side rectifying member 13 and the exhaust port 28.

As shown in FIGS. 1 and 2, the vicinity of the air supply port and the exhaust port of the chamber side wall member 12 are stepped shapes 120 and 129 (hereinafter referred to as the air supply side) whose upper and outer sides are cut out along the periphery. Stepped portion 120 and exhaust side stepped portion 129.). Thereby, a flow path for guiding gas is formed between these stepped portions 120 or 129 and the upper chamber member 11, and as a flow path for guiding gas to the epitaxial film forming chamber upper portion 14 on the air supply port side, On the exhaust port side, it is used as a flow path for exhausting gas from the epitaxial film forming chamber upper part 14.
In the supply side step 120 of the supply side chamber side wall member 12, the vertical wall surface 121 is configured as a collision wall with which the gas introduced into the chamber 10 through the rectifying member 23 collides. By introducing the gas introduced into the chamber 10 into the chamber 10 by colliding with the collision wall 121, the gas is diffused.

  As shown in FIG. 2, the supply-side step 120 on the supply side has a width that is sufficiently longer than the width of the rectifying member 23, in other words, a width that is sufficiently longer than the width of the gas flow path immediately before reaching the chamber 10. Thus, the chamber side wall member 12 is formed. And the side wall member 126 of the shape which fills the edge part of the air supply side level | step-difference part 120 at the both ends is arrange | positioned. The side wall member 126 is a detachable quartz block, and is a member for configuring the side wall 127 that defines the flow path of the gas flowing into the epitaxial film forming chamber upper portion 14 in a desired posture.

  The side wall member 126 is formed in a shape corresponding to the shape of the end portion of the air supply side step portion 120 such that one side is fitted or hooked to the end portion of the air supply side step portion 120. It is installed according to the end of the air supply side step 120. And when it arrange | positions in this way, the shape of the other side is prescribed | regulated so that the side wall 127 of the other side of the side wall member 126 may become a surface which prescribes | regulates the side surface of a gas flow path.

  As shown in FIG. 3, the shape (posture) of the side wall 127 is such that the flow direction of the gas flowing through the rectifying member 23 and the first angle θ1 formed by the side wall 127 of the side wall member 126 are as shown in FIG. As shown, the angle θ2 is defined by the vertical plane of the side wall 127. 3 and 4, the side wall member 126 disposed at the right end of the air supply side step 120 will be described as an example. The side wall member disposed at the left end portion of the supply side stepped portion 120 has a symmetrical shape with the side wall member 126 shown in FIGS. 3 and 4.

  In FIG. 3, the surface ABCD is a surface corresponding to a side wall when the side wall of the rectifying member 23 is linearly extended as it is, and is the same direction as the flow direction of the gas supplied through the rectifying member 23. It is the surface extended | stretched. Further, the surface ABOO ′ is a surface defined by connecting the center O (O ′) of the wafer W placed on the susceptor 26 and the side wall end portion AB of the rectifying member 23, as shown in FIG. This is a surface corresponding to the stepped portion side wall 122 of the air supply side stepped portion 120 of the conventional chamber side wall member 12. The surface ABGH is a surface formed by the side wall 127 of the side wall member 126, and is a surface that defines the flow path of the gas supplied to the chamber 10 in the epitaxial growth apparatus 1 of the present embodiment.

Therefore, the first angle θ1 indicating the posture of the side wall 127 of the side wall member 126 is an angle formed by the surface ABGH (side wall 127) and the surface ABCD (the direction in which the supplied gas flows).
In the chamber 10 of the epitaxial growth apparatus 1 of the present embodiment, this angle θ1 is defined as 0 ≦ θ1 <angle OAC. That is, the side wall 127 of the side wall member 126 has an angle in the horizontal plane within a range of an angle formed by the surface ABOO ′ from an angle formed by the surface ABCD (including a case parallel to the surface ABCD. Including a case parallel to the surface ABOO ′. Not).

In FIG. 4, a surface ABOO ′ is a surface defined by connecting the center O (O ′) of the wafer W placed on the susceptor 26 and the side wall end AB of the rectifying member 23 as in FIG. 3. The surface corresponding to the stepped portion side wall 122 of the air supply side stepped portion 120 of the conventional chamber side wall member 12 as shown in FIG. The surface JBKM is a surface formed by the side wall 127 of the side wall member 126, and is a surface that defines the flow path of the gas supplied to the chamber 10 in the epitaxial growth apparatus 1 of the present embodiment.
As shown in FIG. 4, the second angle θ2 indicating the posture of the side wall 127 of the side wall member 126 indicates the inclination of the surface JBKM (side wall 127) from the vertical plane.
In the chamber 10 of the epitaxial growth apparatus 1 of the present embodiment, this angle θ2 is defined as 0 ° ≦ θ2 ≦ 60 °.

The forms of the side walls 127, that is, the angles θ1 and θ2 that define the posture of the side wall 127 of the side wall member 126 are set to appropriate values according to the epitaxial growth conditions. During the epitaxial growth process, side wall members 126 that realize appropriate angles θ1 and θ2 according to the epitaxial growth conditions are installed on both sides of the supply side step portion 120 of the chamber side wall member 12, and epitaxial growth is performed.
Hereinafter, the example of the specific form of the side wall member 126 is shown as Example 1-Example 3. FIG.

The side wall member 126a as Example 1 is demonstrated with reference to FIG.5 and FIG.6.
FIG. 5 is a diagram schematically showing a configuration in the vicinity of the air supply portion of the chamber 10 of the epitaxial growth apparatus 1 in which the side wall member 126a is arranged, and FIG. 6 is a diagram for explaining the gas flow in the air supply portion. It is.
As shown in FIGS. 5 and 6, the side wall member 126a is a side wall member having a side wall 127a in which the angle θ1 in the horizontal plane with respect to the gas flow direction and the angle θ2 with respect to the vertical plane are both 0 °. The angle θ1 = 0 ° with respect to the gas flow direction of the side wall 127a means that the side wall 127a is formed along the gas flow path as shown in FIG.

  When the side wall member 126a having such a shape is disposed in the supply side step portion 120 of the chamber side wall member 12, the flow of gas introduced into the chamber 10 is as shown in FIG. That is, the gas introduced into each region of the rectifying member 23 partitioned by the partition plate 24 collides with the collision wall 121 of the air supply side step portion 120 of the chamber side wall member 12, but the direction is almost the same in plan view. It flows as it is in the original gas flow direction without change. Also in the regions at both ends of the rectifying member 23, the side wall 127a of the side wall member 126a is formed as a surface along the vertical gas flow like the side wall of the rectifying member 23, so that the gas flow 42 flowing in this region is planar. Flows straight and is guided to the upper part 14 of the epitaxial film forming chamber. As a result, as compared with the conventional epitaxial growth apparatus described above with reference to FIGS. 12 and 13, the flow rate of the gas flowing to the peripheral edge of the wafer is increased, and the growth rate in that part is promoted.

As described above, in the side wall member 126a shown in FIGS. 5 and 6, the angle θ1 in the horizontal plane with respect to the gas flow direction of the side wall 127a is 0 °, whereas the conventional angle shown in FIGS. In the configuration, the side wall 127 is a surface extending in the center direction of the wafer, and the angle θ1 with respect to the gas flow direction is an angle OAC (see FIG. 3). Therefore, if the angle θ1 is slightly smaller than the angle OAC, that is, if the angle formed between the side wall 127a and the gas flow path is even smaller than the conventional one, the flow rate of the gas flowing to the peripheral portion of the wafer in the chamber 10 is the conventional. This further increases the effect of increasing the growth rate of epitaxial growth.
Therefore, under the condition that the angle θ2 = 0 ° with the vertical surface of the side wall 127a, the angle θ1 in the horizontal plane with respect to the gas flow direction of the side wall 127a may be 0 ≦ θ1 <angle OAC. It is not limited to the case of θ1 = 0 ° as shown in FIG.

The side wall member 126b as Example 2 will be described with reference to FIGS.
FIG. 7 is a diagram schematically showing a configuration in the vicinity of the air supply unit of the chamber 10 of the epitaxial growth apparatus 1 in which such a side wall member 126b is arranged, and FIG. 8 explains the gas flow in the air supply unit. FIG.
As shown in FIGS. 7 and 8, the side wall member 126b has a side wall 127b in which the angle θ1 in the horizontal plane with respect to the gas flow direction is the same as the conventional angle OAC (see FIG. 3) and the angle θ2 with respect to the vertical plane is 45 °. It is a side wall member which has. The angle θ2 of the side wall 127b with respect to the gas flow direction is larger than 0 ° (θ2> 0 °), which means that the side wall 127b is formed to be inclined along the gas flow path as shown in FIG. means.

  When the side wall member 126b having such a shape is arranged in the supply side step portion 120 of the chamber side wall member 12, the flow of gas introduced into the chamber 10 is as shown in FIG. That is, the gas flow 41 introduced into the region inside the rectifying member 23 partitioned by the partition plate 24 collides with the collision wall 121 of the supply side stepped portion 120 of the chamber side wall member 12, but in plan view. It flows as it is in the original gas flow direction without changing its direction. On the other hand, the gas flow introduced into the regions at both ends of the partition plate 24 of the rectifying member 23 and the gas flow at the end of the rectifying member 23 have a larger flow dew width and a lower flow resistance above the inclined side wall 127b. Therefore, as shown in FIG. 8, the direction in which the side wall 127 b is inclined is changed and introduced into the epitaxial film forming chamber upper part 14. As a result, the amount of gas flowing to the peripheral edge of the wafer increases as compared with the conventional configuration described above with reference to FIGS. Further, the amount of gas flowing to the peripheral portion of the wafer is further increased than the configuration of the first embodiment shown in FIGS. 5 and 6, and in any case, the growth rate of epitaxial growth at the peripheral portion of the wafer is promoted. It will be.

In the side wall member 126b shown in FIGS. 7 and 8, the angle θ2 with respect to the vertical surface of the side wall 127b is 45 °, but in the conventional configuration shown in FIGS. 12 and 13, the side wall 127 is parallel to the vertical surface. The angle θ2 with respect to the vertical plane is 0 ° (see FIG. 4). Therefore, if the angle θ2 is slightly larger than 0 °, that is, if the side wall 127b is slightly inclined with respect to the vertical plane, the flow rate of the gas flowing to the peripheral edge of the wafer is increased as compared with the conventional case, and the growth of epitaxial growth is achieved. The effect of speed increase is obtained.
Therefore, the angle θ2 with respect to the vertical surface of the side wall 127b may be 0 ≦ θ1 <angle OAC, and is not limited to the case of θ1 = 0 ° as shown in FIGS.

The side wall member 126c as Example 3 will be described with reference to FIGS.
FIG. 9 is a diagram schematically showing a configuration in the vicinity of the air supply part of the chamber 10 of the epitaxial growth apparatus 1 in which such a side wall member 126c is arranged, and FIG. 10 explains the gas flow in the air supply part. FIG.
As shown in FIG. 9, the side wall member 126c is a side wall member having a side wall 127c in which the angle θ1 in the horizontal plane with respect to the gas flow direction is 0 ° and the angle θ2 with respect to the vertical plane is 45 °. 1 is a side wall member in which θ1 of 1 and θ2 of Example 2 are combined.
The fact that the angle θ1 of the side wall 127c with respect to the gas flow direction is 0 ° means that the side wall 127c is formed along the gas flow path in the horizontal plane as shown in FIG. That the angle θ2 with respect to the gas flow direction is formed to be larger than 0 ° means that the side wall 127c is formed to be inclined along the gas flow path as shown in FIG.

  When the side wall member 126c having such a shape is arranged in the supply side step portion 120 of the chamber side wall member 12, the flow of gas introduced into the chamber 10 is as shown in FIG. That is, the gas flow 41 introduced into the region inside the rectifying member 23 partitioned by the partition plate 24 collides with the collision wall 121 of the supply side stepped portion 120 of the chamber side wall member 12, but in plan view. It flows as it is in the original gas flow direction without changing its direction. Further, the gas flow introduced into the regions at both ends of the partition plate 24 of the rectifying member 23 is also formed so that the side wall 127c of the side wall member 126c is formed as a surface along the vertical gas flow like the side wall of the rectifying member 23. The gas flow in the dive portion flows as it is and is guided to the upper part 14 of the epitaxial film forming chamber. Further, in the side wall member 126c of this form, the flow direction of the gas flow introduced into the regions at both ends of the partition plate 24 of the flow regulating member 23 and the gas flow at the end of the flow straightening member 23 is changed by the inclination of the side wall 127c. And introduced into the upper portion 14 of the epitaxial film forming chamber. As a result, the flow rate of the gas flowing in the peripheral portion of the wafer increases as compared with the conventional configuration described above with reference to FIGS. Further, the gas is guided to the peripheral portion of the wafer more than the configurations of the first and second embodiments shown in FIGS. As a result, the growth rate of epitaxial growth at the peripheral edge of the wafer is further promoted.

  In the epitaxial growth apparatus 1 as described above, a gas containing a silane-based gas (SiH 4, SiC 12 H 2, SiHC 13, SiC 14) serving as a source gas and a carrier gas H 2 is introduced into the epitaxial growth apparatus 1 through the pipe 33, and the pipe 34 The flow rate is adjusted by the flow rate adjusters 31 and 32 and introduced into the chamber 10 through the inlet member 21 (see FIG. 1), the baffle 22, and the rectifying member 23. At that time, the gas is diffused by the collision wall 121 of the chamber side wall member 12 and guided to the upper portion 14 of the epitaxial film forming chamber. In particular, a certain amount of the gas flow 42 flowing around the periphery of the rectifying member 23 also flows to the peripheral portion of the wafer due to the action of the side wall 127 of the side wall member 126 disposed in the supply side step portion 120. As a result, the gas is introduced into the chamber 10 in a state where a certain amount of flow rate is secured also at the peripheral edge of the wafer.

Within the chamber 10, the wafer W is disposed on the susceptor 26 and is rotated at a constant rotational speed together with the susceptor 26 by the rotation of the susceptor support 16. Further, the wafer W, the susceptor 26 and the remaining heat ring 25 are heated by the infrared lamp 29. And when the gas introduced into the upper space 14 and the chamber 10 of such a wafer W passes, epitaxial growth will occur on the wafer W and an epitaxial layer will be formed on the wafer.
The gas that has passed over the wafer is exhausted by turning the exhaust side rectifying member 13 and the exhaust port 28.

The film thickness uniformity as a result of actual epitaxial growth by the epitaxial growth apparatus 1 having such a configuration will be described.
Here, epitaxial growth is performed by the epitaxial growth apparatus 1 in which the side wall member 126 of Examples 1 to 3 shown in FIGS. 5 to 10 and the side wall member 126 of the conventional configuration shown in FIGS. For each wafer on which the epitaxial film was formed, the thickness distribution of the epitaxial film in the diameter direction perpendicular to the gas flow path of the wafer was measured.
Hereinafter, the film thickness distribution in each example will be described with reference to FIG.

FIG. 11 is a diagram showing the measurement results.
As shown in FIG. 11, when epitaxial growth is performed with the epitaxial growth apparatus 1 having the side wall member 126 having the conventional configuration, a decrease in the thickness of the epitaxial film is observed at the peripheral edge of the wafer (around 80 mm or more from the center). Also, the difference between the thickness of the epitaxial film at the thickest part (around 30 to 40 mm from the center of the wafer) and the film thickness at the thinnest part (periphery of the wafer) is large. It can be seen that the uniformity is low.

  On the other hand, for the wafer epitaxially grown by the epitaxial growth apparatus 1 having the side wall member 126 of the first to third embodiments described above, the thickness of the epitaxial film at the peripheral edge of the wafer exceeds the thickness of the conventional example. It is observed that the epitaxial growth at the peripheral edge of the wafer was promoted. In addition, the thickness of the epitaxial film at the thickest part (the wafer outermost peripheral part in Example 1; in Examples 2 and 3, around 30 to 40 mm from the center of the wafer) and the thinnest part ( In both cases, the difference between the film thickness and the central portion of the wafer is small as compared with the conventional example, and it can be seen that the uniformity of the film thickness of the epitaxial film is improved. In particular, it can be seen that Example 2 and Example 3 are markedly improved in film thickness uniformity.

  As described above, in the epitaxial growth apparatus 1 having the side wall member 126 of the present embodiment, the gas flow 42 passing through the peripheral portion of the rectifying member 23 of the side wall member 126 disposed in the supply side step portion 120 of the chamber side wall member 12. Due to the influence of the side wall 127, the flow rate of the gas flowing in the peripheral edge portion of the wafer W in the epitaxial film forming chamber upper part 14 is increased. As a result, the growth rate of the Si film is promoted at the peripheral portion of the wafer, the reduction in the Si layer thickness at the peripheral portion of the wafer, which has been conventionally generated, is reduced, and a highly uniform wafer can be manufactured. .

  In addition, this embodiment is described in order to make an understanding of this invention easy, and does not limit this invention at all. Each element disclosed in the present embodiment includes all design changes and equivalents belonging to the technical scope of the present invention, and various suitable modifications can be made.

  For example, the form of the side wall 127 of the side wall member 126 is not limited to the form of the first to third embodiments described above. The angle θ1 formed between the side wall 127 and the gas flow direction is in the range of 0 ° ≦ θ1 ≦ angle OAC, and the angle θ2 formed between the side wall 127 and the vertical plane is in the range of 0 ° ≦ θ2 ≦ 60 °, depending on the epitaxial growth conditions. Any angle value may be used.

FIG. 1 is a vertical sectional view showing the configuration of an epitaxial growth apparatus according to an embodiment of the present invention. 2 is a horizontal cross-sectional view showing the configuration of the epitaxial growth apparatus shown in FIG. 1, and is a cross-sectional view taken along line AA of FIG. FIG. 3 is a view for explaining an angle θ1 with respect to the gas flow direction of the side wall that defines the shape of the side wall of the side wall member of the epitaxial growth apparatus shown in FIGS. FIG. 4 is a view for explaining an angle θ2 with respect to the vertical plane of the side wall that defines the shape of the side wall of the side wall member of the epitaxial growth apparatus shown in FIGS. 1 and 2. FIG. 5 is a diagram showing the configuration of the first embodiment of the side wall member of the epitaxial growth apparatus shown in FIGS. 1 and 2. FIG. 6 is a diagram showing a state of gas flow when the side wall member shown in FIG. 5 is arranged. FIG. 7 is a diagram showing the configuration of the second embodiment of the side wall member of the epitaxial growth apparatus shown in FIGS. FIG. 8 is a diagram showing a state of gas flow when the side wall member shown in FIG. 7 is arranged. FIG. 9 is a diagram showing the configuration of the third embodiment of the side wall member of the epitaxial growth apparatus shown in FIGS. FIG. 10 is a diagram showing a state of gas flow when the side wall member shown in FIG. 9 is arranged. FIG. 11 is a diagram showing the film thickness distribution of the epitaxial film when epitaxial growth is performed by the epitaxial growth apparatus in which the side wall members shown in FIGS. 5 to 10, 12 and 13 are arranged. FIG. 12 is a diagram showing a configuration of a side wall member of a conventional epitaxial growth apparatus. FIG. 13 is a diagram showing a state of gas flow when the side wall member shown in FIG. 12 is arranged.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Epitaxial growth apparatus 10 ... Chamber 11 ... Upper chamber member 12 ... Chamber side wall member
120 ... Supply side step
121 ... Collision wall
122 ... Step side wall
125 ... Partition plate
126 ... Side wall member
127 ... side wall
129: Exhaust side step 13: Lower chamber member 14: Epitaxial film forming chamber upper part 15 ... Epitaxial film forming chamber lower part 21 ... Inlet member 22 ... Baffle 23 ... Rectifying member 24 ... Partition plate 25 ... Preheat ring 26 ... Susceptor 27 ... Exhaust Side rectification member 28 ... exhaust port 29 ... heating lamp 30 ... susceptor support 31,32 ... flow rate regulator 33-35 ... pipe W ... wafer 42,41 ... gas flow

Claims (6)

A chamber for housing the wafer;
An air supply member for supplying a reaction gas to the chamber;
A passage opening provided in a connection portion of the chamber with the air supply member, the reaction gas supplied from the air supply member is formed with a radial direction of the wafer accommodated in the chamber as a longitudinal direction. And an air supply connection portion for supplying the wafer above the wafer,
Sides that form side walls of the passage opening at both ends in the longitudinal direction of the passage opening of the air supply connection, and guide the reaction gas that passes through the vicinity of the end toward the periphery of the wafer A side wall member having a wall surface is disposed ;
The epitaxial growth apparatus characterized in that the side wall surface is formed so as to be inclined in the vertical direction so that the width of the passage opening of the reaction gas becomes wider as it goes vertically upward .   The air supply connection portion is a wall surface that curves and projects from both ends to the center in the longitudinal direction of the passage opening with respect to the direction in which the reaction gas is supplied, and the reaction gas collides The epitaxial growth apparatus according to claim 1, further comprising a curved collision wall surface for diffusing the reaction gas.   The side wall surface of the side wall member has the passage opening portion with respect to a direction in which the reaction gas supplied from the air supply member flows in a direction in which the side wall surface extends toward the wafer accommodated in the chamber. 3. The epitaxial growth apparatus according to claim 1, wherein the epitaxial growth apparatus is formed so as to be shallower than a direction from an end portion of the wafer to a center of the wafer disposed in the chamber. The epitaxial growth apparatus according to any one of claims 1 to 3 , wherein the side wall surface of the side wall member is inclined with respect to a vertical surface in a range of greater than 0 ° and 60 ° or less. Epitaxial growth apparatus according to any one of claims 1 to 4, wherein said side wall member, characterized in that the removable member. Using an epitaxial growth apparatus according to any one of claims 1 to 5 epitaxial wafer manufacturing method characterized by preparing an epitaxial wafer.

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