Vapor phase growth apparatus

Abstract

A vapor phase growth apparatus according to an embodiment includes: a chamber having a head portion at an upper portion thereof and performing wafer processing therein; a process gas supply part which is provided in the head part and supplies a process gas into the chamber; the concave part is arranged on the upper surface of the head part; a translucent member including a portion surrounded by the recess, a first interval between a side surface of the portion and a side surface of the recess being larger than a second interval between a bottom surface of the portion and a bottom surface of the recess; a gas introduction part which is provided in the head part and introduces a gas between the side surface of the recessed part and the side surface of the portion; and a plurality of gas supply parts which are provided in the head part, communicate the recessed part with the chamber, and supply gas to the inside of the chamber.

Description

Technical Field

[0001] The present invention relates to a vapor phase growth device for performing film deposition, heat treatment and other processes on a substrate. Background Art

[0002] In the vapor phase growth apparatus, a process gas including a raw material of the film is introduced into a chamber to form a film on a substrate.

[0003] In the chamber of the vapor phase growth apparatus, an observation port is sometimes provided in order to monitor the temperature of the substrate, the warpage of the substrate, the reflectivity of the substrate, etc. during the film formation process. The temperature of the substrate, the warpage of the substrate, the reflectivity of the substrate, etc. can be optically measured using the observation port having a light-transmitting window and a measuring device provided outside the chamber.

[0004] Byproducts from the process gas containing raw materials may sometimes adhere to the translucent window of the observation port. If the byproducts adhere to the translucent window, the transmittance of light from the translucent window changes. If the transmittance of light from the translucent window changes, the accuracy of optical measurement decreases, which is not preferred. Therefore, it is desirable to suppress the adhesion of byproducts to the translucent window and suppress the decrease in the accuracy of optical measurement.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2013-38196 Summary of the invention

[0008] Problems to be solved by the invention

[0009] An object of the present invention is to provide a vapor phase growth apparatus that suppresses a decrease in the accuracy of optical measurement.

[0010] Means for solving problems

[0011] A vapor phase growth device in one embodiment of the present invention comprises: a chamber having a head at the top, in which a wafer is processed; a process gas supply unit, which is arranged on the above-mentioned head and supplies process gas to the inside of the above-mentioned chamber; a recess, which is arranged on the upper surface of the above-mentioned head; a light-transmitting component, which includes a portion surrounded by the above-mentioned recess, and a first spacing between the side surface of the above-mentioned portion and the side surface of the above-mentioned recess is larger than a second spacing between the bottom surface of the above-mentioned portion and the bottom surface of the above-mentioned recess; a gas inlet unit, which is arranged on the above-mentioned head and introduces gas between the side surface of the above-mentioned recess and the side surface of the above-mentioned portion; and a plurality of gas supply units, which are arranged on the above-mentioned head and connect the above-mentioned recess with the above-mentioned chamber and supply the above-mentioned gas to the inside of the above-mentioned chamber.

[0012] Effects of the Invention

[0013] According to the present invention, it is possible to realize a vapor phase growth apparatus that suppresses degradation of accuracy of optical measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 1 is a schematic cross-sectional view of a vapor phase growth apparatus according to an embodiment.

[0015] Figure 2 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0016] Figure 3 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0017] Figure 4 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0018] Figure 5 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0019] Figure 6 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0020] Figure 7 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment.

[0021] Figure 8 It is a schematic diagram when the shape of the gas exhaust portion according to the embodiment is projected onto the bottom surface of the light-transmitting member.

[0022] Fig. 9 It is an explanatory diagram of the vapor phase growth method according to the first embodiment.

[0023] Fig.10 It is a schematic cross-sectional view of a vapor phase growth apparatus of a comparative example.

[0024] Fig.11 It is a schematic enlarged view of a part of a vapor phase growth apparatus of a comparative example.

[0025] Fig.12 It is an explanatory diagram of the problem of the vapor phase growth apparatus of the comparative example.

[0026] Fig.13 It is an explanatory diagram of the function and effect of the vapor phase growth apparatus according to the embodiment.

[0027] Fig.14 It is an explanatory diagram of the function and effect of the vapor phase growth apparatus according to the embodiment.

[0028] Fig.15 It is an enlarged schematic diagram of a part of the vapor phase growth apparatus according to the first modified example of the embodiment.

[0029] Fig.16 This is a schematic diagram in which the shape of the gas exhaust portion according to the first modified example of the embodiment is projected onto the bottom surface of the light-transmitting member.

[0030] Fig.17 It is an enlarged schematic diagram of a part of the vapor phase growth apparatus according to the second modified example of the embodiment. DETAILED DESCRIPTION

[0031] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0032] In this specification, the same or similar components may be denoted by the same reference numerals.

[0033] In this specification, the direction of gravity when the vapor growth apparatus is set to form a film is defined as "down", and the opposite direction is defined as "up". Therefore, "down" refers to the position in the direction of gravity relative to the reference, and "below" refers to the direction of gravity relative to the reference. In addition, "upper" refers to the position in the opposite direction to the direction of gravity relative to the reference, and "above" refers to the opposite direction to the direction of gravity relative to the reference. In addition, "longitudinal" refers to the direction of gravity.

[0034] In this specification, “process gas” is a general term for gas used to form a film, and is a concept including, for example, source gas, assist gas, dopant gas, carrier gas, and a mixed gas thereof.

[0035] The vapor phase growth device of the embodiment comprises: a chamber having a head at the top, in which a wafer is processed; a process gas supply unit, which is arranged at the head, and supplies process gas to the inside of the chamber; a recess, which is arranged on the upper surface of the head; a light-transmitting component, including a portion surrounded by the recess, wherein a first spacing between the side surface of the portion and the side surface of the recess is larger than a second spacing between the bottom surface of the portion and the bottom surface of the recess; a gas inlet unit, which is arranged at the head, and introduces gas between the side surface of the recess and the side surface of the portion; and a plurality of gas supply units, which are arranged at the head, connect the recess with the chamber, and supply gas to the inside of the chamber.

[0036] Figure 1 Schematic cross-sectional view of a vapor phase growth apparatus according to an embodiment. The vapor phase growth apparatus according to the embodiment is a vapor phase growth apparatus 100. The vapor phase growth apparatus 100 according to the first embodiment is, for example, a monolithic epitaxial growth apparatus that epitaxially grows a single-crystalline silicon carbide film on a single-crystalline silicon carbide substrate.

[0037] The vapor phase growth apparatus 100 of the embodiment includes a chamber 10, a support 12, a rotating body 14, a lower heater 16, an upper heater 18, a cover 20, and a heat insulator 22. The chamber 10 includes a head 30, a lower plate 32, a side wall 34, and an observation port 44. The head 30 includes a plurality of process gas supply parts 36, a buffer chamber 38 (recess), a purge gas introduction part 40 (gas introduction part), and a plurality of purge gas supply parts 42 (gas supply parts). The observation port 44 includes a light-transmitting window 46 (light-transmitting member) and a fixing part 48. The lower plate 32 includes a gas exhaust port 52.

[0038] The chamber 10 is made of, for example, stainless steel. Inside the chamber 10, for example, a silicon carbide film is formed on a wafer W. The wafer W is an example of a substrate. The wafer W is, for example, a semiconductor wafer. The wafer W is, for example, a single crystal silicon carbide wafer.

[0039] The chamber 10 includes a head 30 , a lower plate 32 , side walls 34 , and a viewing port 44 .

[0040] The head portion 30 includes a plurality of process gas supply portions 36, a buffer chamber 38 (recessed portion), a purge gas introduction portion 40, and a plurality of purge gas supply portions 42. The lower plate 32 includes a gas exhaust port 52.

[0041] The process gas supply unit 36 ​​includes, for example, a through hole extending from the upper surface of the head 30 to the inside of the chamber 10. The process gas supply unit 36 ​​has a function of supplying process gas to the inside of the chamber 10. The process gas supplied from the plurality of process gas supply units 36 includes, for example, a source gas for forming a silicon carbide film on the wafer W.

[0042] The buffer chamber 38 is a recessed portion provided in the upper portion of the head portion 30. The buffer chamber 38 is provided on the upper surface of the head portion 30. The buffer chamber 38 is provided below the observation port 44.

[0043] The purge gas introduction part 40 has, for example, a through hole that reaches the side of the buffer chamber 38 from the side of the head 30. The purge gas introduction part 40 has a function of introducing a purge gas (gas) from the side of the buffer chamber 38 into the buffer chamber 38. The purge gas introduction part 40 introduces the purge gas between the side of the buffer chamber 38 and the side of the convex portion 46a of the translucent window 46. By introducing the purge gas into the buffer chamber 38, it is possible to suppress the adhesion of byproducts to the translucent window 46 of the observation port 44.

[0044] The plurality of purge gas supply parts 42 include, for example, through holes extending from the bottom surface of the buffer chamber 38 to the interior of the chamber 10. The plurality of purge gas supply parts 42 extend, for example, in the direction of gravity.

[0045] The purge gas supply unit 42 has a function of supplying purge gas from the buffer chamber 38 to the interior of the chamber 10 . The purge gas supply unit 42 also functions as a path for light to pass when optically measuring the state of the wafer W. The wafer W is disposed in the extending direction of the purge gas supply unit 42 .

[0046] The process gas supply portion 36 is, for example, a hole that passes through the head portion 30. For example, a part or all of the process gas supply portion 36 may also be tubular. The purge gas introduction portion 40 is, for example, a hole that passes through the side of the head portion 30. For example, a part or all of the purge gas introduction portion 40 may also be tubular. The purge gas supply portion 42 is, for example, a hole that passes through the head portion 30. For example, a part or all of the purge gas supply portion 42 may also be tubular.

[0047] The observation port 44 is provided above the head 30. For example, the temperature of the wafer W, the warpage of the wafer W, the reflectivity of the wafer W, etc. can be optically measured using a measuring instrument (not shown) provided outside the chamber 10 and the observation port 44 having the light-transmitting window 46.

[0048] The gas exhaust port 52 is provided in the lower plate 32. The gas exhaust port 52 has a function of exhausting a process gas, a by-product gas, a purge gas, etc. from the inside of the chamber 10 to the outside.

[0049] The side wall 34 is provided between the head 30 and the lower plate 32. The side wall 34 has a cylindrical shape, for example.

[0050] The holder 12 is provided inside the chamber 10 . A wafer W can be mounted on the holder 12 .

[0051] The bracket 12 is placed on the upper part of the rotating body 14. The rotating body 14 is fixed to a rotating shaft (not shown).

[0052] The rotating shaft can be rotated by a rotation drive mechanism (not shown). By rotating the rotating shaft, the holder 12 can be rotated. By rotating the holder 12, the wafer W mounted on the holder 12 can be rotated.

[0053] The lower heater 16 is provided below the holder 12. The lower heater 16 is provided inside the rotating body 14. The lower heater 16 heats the wafer W held by the holder 12 from below.

[0054] The upper heater 18 is provided between the cover 20 and the side wall 34. The upper heater 18 is located above the support 12. The upper heater 18 heats the wafer W held by the support 12 from above.

[0055] The cover 20 has, for example, a cylindrical shape. The cover 20 has, for example, a function of preventing the process gas from contacting the upper heater 18. The cover 20 has, for example, a function of rectifying the process gas.

[0056] The heat insulator 22 is provided between the upper heater 18 and the side wall 34 .

[0057] Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 as well as Figure 7 It is a schematic enlarged view of a part of the vapor growth apparatus according to the embodiment. Figures 2 to 7 It is an enlarged schematic cross-sectional view of the observation port 44 and its vicinity of the vapor phase growth apparatus 100 .

[0058] Figure 2 It is a top view of the vicinity of the observation port 44 . Figure 3 yes Figure 2 AA' section. Figure 4 yes Figure 2 BB' cross section. Figure 5 yes Figure 3 CC' section. Figure 6 yes Figure 3 DD' section. Figure 7 yes Figure 3 EE' section.

[0059] The observation port 44 includes a light-transmitting window 46 (light-transmitting member), a fixing portion 48 , and a sealing member 50 .

[0060] The light-transmitting window 46 has a convex portion 46 a and a flange 46 b . The light-transmitting window 46 is fixed to the head 30 via a fixing portion 48 .

[0061] The light-transmitting window 46 is formed of a material that is transparent to light. The light-transmitting window 46 is formed of, for example, quartz glass.

[0062] The flange 46b is provided at the end of the buffer chamber 38. A sealing member 50 is provided between the flange 46b and the head 30. The sealing member 50 has a function of maintaining the airtightness of the interior of the chamber 10. The sealing member 50 is, for example, an O-ring.

[0063] like Figure 3 as well as Figure 4 As shown, the convex portion 46a is disposed inside the buffer chamber 38. Figure 5 as well as Figure 6 As shown, the convex portion 46a is surrounded by the buffer chamber 38. The side surface and the bottom surface of the convex portion 46a are surrounded by the buffer chamber 38.

[0064] The side surface of the convex portion 46a and the side surface of the buffer chamber 38 have a first gap ( Figure 3 as well as Figure 4 The first interval d1 is, for example, not less than 1 mm and not more than 5 mm.

[0065] In addition, the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 have a second gap ( Figure 3 as well as Figure 4 d2 in the figure.

[0066] The second distance d2 is equal to or less than the first distance d1. The second distance d2 is, for example, not less than 0.2 mm and not more than 2 mm.

[0067] like Figure 3 As shown, the purge gas introduction portion 40 is provided on the side of the buffer chamber 38. The purge gas introduction portion 40 allows the outside of the head 30 to communicate with the buffer chamber 38. The purge gas introduction portion 40 is, for example, a hole that penetrates the head 30.

[0068] like Figure 3 As shown, the third gap ( Figure 3 d3) is greater than the second distance ( Figure 3 In addition, if Figure 6 As shown, the purge gas introduction portion 40 is opposed to a side surface of the convex portion 46 a , for example.

[0069] like Figure 3 as well as Figure 7 As shown, the plurality of purge gas supply units 42 include a first purge gas supply unit 42a, a second purge gas supply unit 42b, and a third purge gas supply unit 42c. In the embodiment, the plurality of purge gas supply units 42 are three as an example, but the plurality of purge gas supply units 42 may be two or more.

[0070] The first purge gas supply part 42a, the second purge gas supply part 42b, and the third purge gas supply part 42c reach the inside of the chamber 10 from the bottom surface of the buffer chamber 38. In other words, one end of the first purge gas supply part 42a, the second purge gas supply part 42b, and the third purge gas supply part 42c is located at the bottom surface of the buffer chamber 38, and the other end is located at the bottom surface of the head 30.

[0071] like Figure 7 As shown, the shape of the purge gas supply portion 42 is, for example, circular in a cross section perpendicular to the extending direction of the purge gas supply portion 42. The shape of the purge gas supply portion 42 in the cross section is not limited to circular, and may be, for example, elliptical or polygonal.

[0072] The second gap ( Figure 3 as well as Figure 4 d2) is smaller than the maximum opening width of the purge gas supply portion 42 ( Figure 3 , Figure 4 , Figure 7 In addition, the first gap (d4) between the side surface of the convex portion 46a and the side surface of the buffer chamber 38 Figure 3 as well as Figure 4 d1) is smaller than the maximum opening width ( Figure 3 , Figure 7 The maximum opening width d4 of the purge gas supply portion 42 is, for example, not less than 10 mm and not more than 50 mm.

[0073] In addition, the maximum opening width d4 of the purge gas supply portion 42 is defined as the maximum distance between any two points on the circumference of the purge gas supply portion 42 in a cross section in a direction perpendicular to the extending direction of the purge gas supply portion 42. For example, as in the purge gas supply portion 42 of the embodiment, when the shape of the purge gas supply portion 42 in the cross section is circular, the maximum opening width d4 of the purge gas supply portion 42 is the diameter of the circle.

[0074] The bottom surface of the convex portion 46 a faces the entire area of ​​the openings of the plurality of purge gas supply portions 42 in the extending direction of the purge gas supply portions 42 .

[0075] Figure 8 Schematic diagram showing the shape of the gas exhaust portion of the embodiment projected onto the bottom surface of the light-transmitting member. Figure 8 As shown in FIG. 1 , when the shape of the purge gas supply portion 42 is projected onto the bottom surface of the light-transmitting window 46 at an equal magnification in the extending direction of the purge gas supply portion 42, the projected shape of the purge gas supply portion 42 is included in the bottom surface of the light-transmitting window 46. In the extending direction of the purge gas supply portion 42, the shapes of the first purge gas supply portion 42a, the second purge gas supply portion 42b, and the third purge gas supply portion 42c projected onto the bottom surface of the light-transmitting window 46 are respectively a projection shape 42ax, a projection shape 42bx, and a projection shape 42cx.

[0076] The projection shape 42ax, the projection shape 42bx, and the projection shape 42cx are all included in the bottom surface of the light-transmitting window 46. In other words, the projection shape 42ax, the projection shape 42bx, and the projection shape 42cx are all located inside the outer periphery of the bottom surface of the light-transmitting window 46.

[0077] like Figure 8 As shown, the distances between the projection shape 42ax, the projection shape 42bx, and the projection shape 42cx and the outer periphery of the bottom surface of the light-transmitting window 46 are the fifth distance d5 or the sixth distance d6. Figure 3 as well as Figure 4As shown, the distance between the convex portion 46a and the purge gas supply portion 42 in the direction perpendicular to the extending direction of the purge gas supply portion 42 is also the fifth distance d5 or the sixth distance d6. The fifth distance d5 and the sixth distance d6 are, for example, greater than the second distance d2.

[0078] Next, an example of a vapor phase growth method using the vapor phase growth apparatus 100 of the embodiment will be described. Hereinafter, a case where a single crystal silicon carbide film doped with nitrogen as an n-type impurity is formed on the surface of a single crystal silicon carbide wafer W will be described as an example. In addition, a case where the temperature of the surface of the wafer W is measured using a measuring device provided outside the observation port 44 and the chamber 10 will be described as an example.

[0079] Fig. 9 4 is an explanatory diagram of the vapor phase growth method according to the embodiment. A measuring device 54 is provided above the observation port 44. The measuring device 54 is, for example, a pyrometer capable of measuring the temperature of the surface of the wafer W.

[0080] First, the wafer W is placed on the holder 12. The wafer W is a single crystal silicon carbide wafer.

[0081] Next, the wafer W is rotated by a rotation drive mechanism (not shown). Then, the wafer W is heated by the lower heater 16 and the upper heater 18 .

[0082] Then, if Fig. 9 As shown, the process gas G1 is supplied into the chamber 10 from a plurality of process gas supply units 36 .

[0083] The process gas G1 is, for example, a mixed gas including a silicon source gas, a carbon source gas, an n-type impurity dopant gas, an auxiliary gas, and a carrier gas. The silicon source gas is, for example, silane gas (SiH4). The carbon source gas is, for example, propane gas (C3H8). The n-type impurity dopant gas is, for example, nitrogen gas (N2). The auxiliary gas is, for example, hydrogen chloride gas (HCl). The carrier gas is, for example, argon gas (Ar) or hydrogen gas (H2).

[0084] A single-crystalline silicon carbide film doped with nitrogen as an n-type impurity is formed on the surface of the wafer W by decomposition and reaction of the process gas G1.

[0085] For example, while supplying the process gas G1 into the chamber 10 , the purge gas G2 is introduced into the buffer chamber 38 from the purge gas introduction unit 40 . The purge gas G2 introduced into the buffer chamber 38 is supplied from the buffer chamber 38 to the chamber 10 through the plurality of purge gas supply units 42 .

[0086] By flowing the purge gas G2 from the buffer chamber 38 into the chamber 10, the process gas G1 is prevented from flowing into the buffer chamber 38. In addition, by flowing the purge gas G2 from the buffer chamber 38 into the chamber 10, turbulence of the process gas G1 in the chamber 10 is prevented. The purge gas G2 is, for example, hydrogen gas or argon gas.

[0087] For example, during the process of forming a silicon carbide film, the temperature of the surface of the wafer W is measured by receiving light passing through the purge gas supply unit 42 and the light-transmitting window 46 through the measuring device 54. The temperature of the surface of the wafer W is measured using the observation port 44 and the measuring device 54. By providing three purge gas supply units 42, for example, the temperatures of three locations, namely, the center of the wafer W, the periphery of the wafer W, and between the center and periphery of the wafer W, can be measured simultaneously.

[0088] like Fig. 9 As shown, during the process of forming the silicon carbide film, the exhaust gas G3 is exhausted from the gas exhaust port 52 to the outside of the chamber 10. The exhaust gas G3 includes, for example, unreacted process gas G1 and purge gas G2.

[0089] After the single crystal silicon carbide film is formed, for example, the supply of the process gas G1 to the chamber 10 and the supply of the purge gas G2 to the buffer chamber 38 are stopped. In addition, the heating of the lower heater 16 and the upper heater 18 is stopped to lower the temperature of the wafer W. Thereafter, the wafer W is unloaded from the chamber 10.

[0090] Next, the operation and effects of the vapor phase growth apparatus 100 according to the embodiment will be described.

[0091] Fig.10 It is a schematic cross-sectional view of a vapor phase growth apparatus of a comparative example. Fig.11 It is a schematic enlarged view of a part of a vapor phase growth apparatus of a comparative example. Fig.10 is related to the implementation method Figure 1 The corresponding figure. Fig.11 is related to the implementation method Figure 3 The corresponding figure.

[0092] The vapor phase growth apparatus of the comparative example is the vapor phase growth apparatus 900. Fig.10 as well as Fig.11 As shown, the vapor phase growth apparatus 900 of the comparative example is different from the vapor phase growth apparatus 100 of the embodiment in that the light-transmitting window 46 does not have the convex portion 46a. The light-transmitting window 46 of the comparative example is in the shape of a flat plate.

[0093] Fig.12 It is an explanatory diagram of the problem of the vapor phase growth apparatus of the comparative example. Fig.12 is with Fig.11 The corresponding figure. Fig.122 shows the flow of the purge gas G2 or the process gas G1 when a film is formed using the vapor phase growth apparatus 900 .

[0094] like Fig.12 As shown in FIG. 1 , the flow velocity of the purge gas G2 introduced into the buffer chamber 38 from the purge gas introduction portion 40 in the horizontal direction is relatively large. Therefore, the flow rate of the purge gas G2 flowing to the first purge gas supply portion 42a farthest from the purge gas introduction portion 40 becomes large. In addition, the flow rate of the purge gas G2 flowing to the third purge gas supply portion 42c closest to the purge gas introduction portion 40 becomes small.

[0095] The flow rate of the purge gas G2 flowing to the first purge gas supply part 42a is relatively large, and the flow rate of the purge gas G2 flowing to the third purge gas supply part 42c is relatively small. Therefore, the purge gas G2 and the process gas G1 may flow back from the third purge gas supply part 42c to the buffer chamber 38.

[0096] If the process gas G1 containing the source gas flows into the buffer chamber 38, the process gas G1 may decompose or react in the buffer chamber 38, causing the by-product 56 to adhere to the lower surface of the light-transmitting window 46. If the by-product 56 adheres to the light-transmitting window 46, the transmittance of the light of the light-transmitting window 46 changes. If the transmittance of the light of the light-transmitting window 46 changes, the accuracy of the optical measurement decreases, which is not preferred. Fig.12 In the embodiment, byproduct 56 is attached to the position of each of the first purge gas supply part 42a, the second purge gas supply part 42b, and the third purge gas supply part 42c of the light-transmitting window 46 in the extending direction. However, byproduct 56 may be attached to the position of any one of the first purge gas supply part 42a, the second purge gas supply part 42b, and the third purge gas supply part 42c in the extending direction.

[0097] It is considered that the difference in the flow rate of the purge gas G2 flowing to the first purge gas supply part 42a, the second purge gas supply part 42b, and the third purge gas supply part 42c occurs because the combined conductance from the purge gas introduction part 40 to the inside of the chamber 10 is large. Therefore, it is considered that the purge gas G2 and the process gas G1 flow back from the third purge gas supply part 42c to the buffer chamber 38 because the combined conductance from the purge gas introduction part 40 to the inside of the chamber 10 is large.

[0098] Fig.13 as well as Fig.14 It is an explanatory diagram of the function and effect of the vapor phase growth apparatus according to the embodiment. Fig.13 is with Figure 6 The corresponding figure. Fig.14 is with Figure 3 The corresponding figure. Fig.13 as well as Fig.14 2 shows the flow of the purge gas G2 when a film is formed using the vapor phase growth apparatus 100 .

[0099] like Fig.13 as well as Fig.14 As shown, the purge gas G2 supplied horizontally from the purge gas inlet 40 to the buffer chamber 38 flows to the purge gas supply part 42 through the gap between the convex portion 46a of the light-transmitting window 46 and the buffer chamber 38. By providing the convex portion 46a, the flow rate of the purge gas G2 becomes smaller than that of the comparative example. This is because by providing the convex portion 46a, the combined conductance from the purge gas inlet 40 to the inside of the chamber 10 becomes smaller than that of the comparative example.

[0100] By reducing the combined conductance from the purge gas introduction portion 40 to the inside of the chamber 10, the flow rates of the purge gas G2 flowing to the first purge gas supply portion 42a, the second purge gas supply portion 42b, and the third purge gas supply portion 42c are easily equalized compared to the case of the comparative example. In particular, by setting the second distance d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 to be less than the first distance d1 between the side surface of the convex portion 46a and the side surface of the buffer chamber 38, the flow rate of the purge gas G2 in the first purge gas supply portion 42a farthest from the purge gas introduction portion 40 and the flow rate of the purge gas G2 in the third purge gas supply portion 42c closest to the purge gas introduction portion 40 can be equalized.

[0101] Therefore, it is possible to suppress the purge gas G2 and the process gas G1 from flowing back from the purge gas supply unit 42 into the buffer chamber 38. Therefore, it is possible to suppress the byproduct 56 from adhering to the light-transmitting window 46, and to suppress a decrease in the accuracy of optical measurement.

[0102] From the viewpoint of suppressing the backflow of the purge gas G2 and the process gas G1 into the buffer chamber 38, it is preferable that the second distance d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is smaller than the first distance d1 between the side surface of the convex portion 46a and the side surface of the buffer chamber 38. The conduction between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is reduced, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 is easily equalized.

[0103] From the viewpoint of suppressing the backflow of the purge gas G2 and the process gas G1 into the buffer chamber 38, the second distance d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is preferably 2 mm or less, and more preferably 1 mm or less. The conduction between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 becomes small, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 is easily equalized.

[0104] From the viewpoint of suppressing the backflow of the purge gas G2 and the process gas G1 into the buffer chamber 38, it is preferred that the second interval d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is smaller than the maximum opening width d4 of the purge gas supply portion 42. The conduction between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is reduced, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply portions 42 is easily equalized.

[0105] From the viewpoint of suppressing the purge gas G2 and the process gas G1 from flowing back into the buffer chamber 38, it is preferable that the bottom surface of the convex portion 46a and the entire area of ​​the openings of the plurality of purge gas supply units 42 are opposed to each other in the extension direction of the purge gas supply units 42. In addition, from the viewpoint of suppressing the purge gas G2 and the process gas G1 from flowing back into the buffer chamber 38, it is preferable that when the shapes of the plurality of purge gas supply units 42 are projected onto the bottom surface of the convex portion 46a at equal multiples in the extension direction of the plurality of purge gas supply units 42, the projected shapes are included in the bottom surface of the convex portion 46a. The conduction between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is reduced, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 is easily equalized.

[0106] From the viewpoint of suppressing the backflow of the purge gas G2 and the process gas G1 into the buffer chamber 38, it is preferred that when the shapes of the plurality of purge gas supply units 42 are equally projected onto the bottom surface of the convex portion 46a in the extending direction of the plurality of purge gas supply units 42, the fifth distance d5 and the sixth distance d6 between the projected shape and the outer periphery of the bottom surface of the convex portion 46a are greater than the second distance d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38. The conduction between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38 is reduced, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 is easily equalized.

[0107] From the viewpoint of suppressing the backflow of the purge gas G2 and the process gas G1 into the buffer chamber 38, it is preferred that the third distance d3 between the purge gas introduction portion 40 and the bottom surface of the buffer chamber 38 in the extension direction of the purge gas supply portion 42 is greater than the second distance d2 between the bottom surface of the convex portion 46a and the bottom surface of the buffer chamber 38. The conduction between the purge gas introduction portion 40 and the third purge gas supply portion 42c closest to the purge gas introduction portion 40 is reduced, and the flow rate of the purge gas G2 flowing to the plurality of purge gas supply portions 42 is easily equalized.

[0108] Fig.15 It is an enlarged schematic diagram of a part of the vapor phase growth apparatus according to the first modified example of the embodiment. Fig.15 is related to the implementation method Figure 3 The corresponding figure. Fig.16 This is a schematic diagram in which the shape of the gas exhaust portion according to the first modified example of the embodiment is projected onto the bottom surface of the light-transmitting member. Fig.16 is related to the implementation method Figure 8 The corresponding figure.

[0109] like Fig.15 As shown in FIG. 1 , the vapor phase growth apparatus of the first modification example is different from the vapor phase growth apparatus of the embodiment in that the bottom surface of the convex portion 46a is not opposite to a part of the opening of the purge gas supply unit 42. Fig.16 As shown, the difference between the vapor phase growth device of the first variant and the vapor phase growth device of the embodiment is that, when the shape of the purge gas supply part 42 is projected onto the bottom surface of the translucent window 46 at an equal multiple in the extension direction of the purge gas supply part 42, a part of the projected shape of the purge gas supply part 42 is not included in the bottom surface of the translucent window 46.

[0110] In the vapor phase growth apparatus of the first modification, the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 can be easily equalized, compared with the vapor phase growth apparatus 900 of the comparative example.

[0111] Fig.17 It is an enlarged schematic diagram of a part of the vapor phase growth apparatus according to the second modified example of the embodiment. Fig.17 is related to the implementation method Figure 6 The corresponding figure.

[0112] like Fig.17 As shown, the vapor phase growth apparatus of the second modification example is different from the vapor phase growth apparatus 100 of the embodiment in that the purge gas introduction portion 40 is not opposed to the side surface of the convex portion 46 a .

[0113] In the vapor phase growth apparatus of the second modification, the flow rate of the purge gas G2 flowing to the plurality of purge gas supply units 42 can be easily equalized, compared with the vapor phase growth apparatus 900 of the comparative example.

[0114] The embodiments of the present invention have been described above with reference to specific examples. The above embodiments are merely given as examples and do not limit the present invention. In addition, the constituent elements of each embodiment may be appropriately combined.

[0115] In the embodiment, the case of forming a single-crystalline silicon carbide film is described as an example, but the present invention can also be applied to a vapor phase growth apparatus for forming a film other than a single-crystalline silicon carbide film.

[0116] Furthermore, in the embodiment, a single-crystal silicon carbide wafer is described as an example of a substrate, but the substrate is not limited to a single-crystal silicon carbide wafer.

[0117] In the embodiments, the description of the device configuration, manufacturing method, optical measurement method, etc., which are not directly necessary in the description of the present invention, is omitted, but the necessary device configuration, manufacturing method, optical measurement method, etc. can be appropriately selected and used. In addition, all vapor phase growth devices that have the elements of the present invention and can be appropriately designed and changed by those skilled in the art are included in the scope of the present invention. The scope of the present invention is defined by the scope of the patent claims and the scope of their equivalents.

[0118] Explanation of symbols:

[0119] 10: chamber; 12: support; 30: head; 36: process gas supply part; 38: buffer chamber (recess); 40: purge gas inlet part (gas inlet part); 42: purge gas supply part (gas supply part); 46: light-transmitting window (light-transmitting component); 46a: convex part (part); 54: measuring instrument; 100: vapor phase growth device; W: wafer (substrate); G2: purge gas (gas); d1: first interval; d2: second interval; d3: third interval; d4: maximum opening width.

Claims

1. A vapor growth device comprising: a chamber having a head at the upper portion, inside which the processing of the wafer is performed; A process gas supply unit is provided at the head portion and supplies process gas to the interior of the chamber; A recessed portion is provided on the upper surface of the head; a light-transmitting member including a portion surrounded by the concave portion, wherein a first distance between a side surface of the portion and a side surface of the concave portion is greater than a second distance between a bottom surface of the portion and a bottom surface of the concave portion; a gas introduction portion, provided on the head portion, for introducing gas between a side surface of the recess and a side surface of the portion; and A plurality of gas supply parts are provided in the head portion, connect the recessed portion with the chamber, and supply the gas into the chamber.

2. The vapor phase growth apparatus according to claim 1, wherein: The bottom surface of the portion faces the entire area of ​​the openings of the plurality of gas supply parts.

3. The vapor phase growth apparatus according to claim 1, wherein: The second interval is smaller than a maximum opening width of the plurality of gas supply parts.

4. The vapor phase growth apparatus according to claim 2, wherein: The second interval is smaller than a maximum opening width of the plurality of gas supply parts.

5. The vapor phase growth apparatus according to claim 1, wherein: The vapor phase growth apparatus further includes a measuring device provided above the light-transmitting member.

6. The vapor phase growth apparatus according to claim 2, wherein: The vapor phase growth apparatus further includes a measuring device provided above the light-transmitting member.

7. The vapor growth apparatus according to claim 1, wherein: The light-transmitting member further includes a flange, and the flange is placed on an end portion of the recessed portion.

8. The vapor growth apparatus according to claim 2, wherein: The light-transmitting member further includes a flange, and the flange is placed on an end portion of the recessed portion.

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