JP2013053355A - Vapor phase deposition apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor phase deposition apparatus that can eliminate in-plane temperature distribution of a surface of a substrate and can boost yield by improving the within-wafer non-uniformity of a thin film to be formed on the surface of the substrate.SOLUTION: In the vapor phase deposition apparatus, the substrate 22 is held on a substrate-holding recessed portion 23 provided on a substrate-holding member 20, the substrate is heated through the substrate-holding member that is heated by a heater, and a feedstock gas is supplied on the substrate to form the thin film on the surface of the substrate. The substrate-holding recess includes: a flat-surface portion 26 formed in parallel with a back surface of the substrate; a substrate-holding projection portion 27 that projects upward from the flat-surface portion and on the upper end of which a substrate-mounting portion 27a is provided; and a recessed groove portion 28 provided on a flat-surface portion adjacent to the substrate-holding projection portion.

Description

  The present invention relates to a vapor phase growth apparatus, and more particularly to a vapor phase growth apparatus that heats a substrate via a substrate holding member heated by a heating unit.

  In a vapor phase growth apparatus that heats a substrate via a substrate holding member heated by a heating means, a plurality of substrates are provided between the substrate holding member (substrate holder) and the substrate in order to improve temperature uniformity and temperature reproducibility of the substrate. There is known a substrate support structure in which a small support protrusion is interposed to minimize the contact heat conduction by minimizing the contact area between the substrate holding member and the substrate (see, for example, Patent Document 1). .

JP 2008-91615 A

  However, in the substrate support structure described in Patent Document 1, it is possible to make the entire substrate temperature uniform, but the temperature of the portion in contact with the substrate holding member via the support protrusion and the surrounding temperature is high. Therefore, the thin film formed in this portion cannot be used as a product, and there is a problem that the yield decreases.

  Therefore, the present invention further improves the temperature uniformity of the substrate to eliminate the in-plane temperature distribution on the substrate surface, and improves the in-plane uniformity of the thin film formed on the substrate surface to improve the yield. It aims to provide a growth device.

  In order to achieve the above object, the vapor phase growth apparatus of the present invention holds a substrate in a substrate holding recess provided in the substrate holding member and heats the substrate via the substrate holding member heated by a heating means. In the vapor phase growth apparatus for supplying a source gas onto the substrate to form a thin film on the surface of the substrate, the substrate holding recess protrudes upward from the flat portion parallel to the back surface of the substrate and the flat portion. And a substrate supporting convex portion provided with a substrate mounting portion at the upper end, and a concave groove portion provided in the planar portion adjacent to the substrate supporting convex portion.

  Furthermore, in the vapor phase growth apparatus of the present invention, the substrate support convex portion is formed in a columnar shape, and the concave groove portion is provided in a ring shape around the columnar substrate support convex portion. It is characterized by.

  According to the vapor phase growth apparatus of the present invention, the distance between the bottom surface of the recessed groove portion provided in the flat surface portion adjacent to the substrate supporting convex portion and the back surface of the substrate is greater than the distance between the flat surface portion and the back surface of the substrate. Therefore, compared to the amount of radiant heating from the flat portion, the amount of radiant heat from the concave groove portion becomes smaller, and the amount of heating around the portion where the temperature tends to rise due to contact with the substrate support convex portion decreases, It is possible to average the temperature of the portion in contact with the substrate support convex portion and the surrounding temperature. In addition, by forming the substrate support convex portion in a cylindrical shape, the contact area between the substrate support convex portion and the substrate can be reduced, and furthermore, a concave groove portion is formed in a ring shape around the cylindrical substrate support convex portion. By providing, it is possible to reduce the amount of heating of the entire periphery of the substrate part in contact with the substrate support convex part, so that the temperature of the part in contact with the substrate support convex part and the temperature in the vicinity thereof can be more reliably averaged. Can do.

It is sectional drawing of the principal part which shows the 1st form example of the vapor phase growth apparatus of this invention. It is a top view which similarly shows the relationship between a board | substrate holding member and a board | substrate. FIG. 3 is a sectional view taken along line III-III in FIG. 2. It is a top view which shows the relationship between the board | substrate holding member in the 2nd example of a vapor phase growth apparatus of this invention, and a board | substrate. It is VV sectional drawing of FIG. It is a top view which shows the relationship between the board | substrate holding member in the 2nd example of a vapor phase growth apparatus of this invention, and a board | substrate. It is VII-VII sectional drawing of FIG.

  First, in the first embodiment shown in FIGS. 1 to 3, the vapor phase growth apparatus shown in the present embodiment is a self-revolving vapor phase growth apparatus having a self-revolving mechanism, and is flattened covered with quartz glass. In the cylindrical chamber 11, a disk-like rotating member 13 supported by a rotating shaft 12 penetrating the bottom surface portion of the chamber 11 is rotatably provided, and a source gas introducing portion 14 is provided at the center upper portion of the chamber 11. A gas discharge part 15 is provided on the outer periphery of the chamber 11. Below the rotating member 13, a heater 16 and a thermometer 17 are provided so as to surround the rotating shaft 12, and a reflector 18 is provided around the heater 16.

  On the outer peripheral portion of the upper surface of the rotating member 13, circular recesses 13 a in plan view are provided at equal intervals in the circumferential direction, and the rolling recesses 19 a and 19 b roll in the respective recesses 13 a. The guide members 21 that rotatably support the substrate holding member 20 via the rolling members 19 are accommodated. A substrate holding recess 23 for holding the substrate 22 is formed on the upper surface of the substrate holding member 20. A ring-shaped fixed gear member 24 provided on the outer periphery of the rotating member 13 is formed on the lower outer periphery of the substrate holding member 20. An external gear 20a is formed that meshes with the internal gear 24a formed in the above. In addition, a cover member 25 that covers each gear is provided on the outer gear 20a and the inner gear 24a.

  The bottom surface of the substrate holding recess 23 includes a flat portion 26 parallel to the back surface of the substrate 22, a plurality of substrate support convex portions 27 protruding upward from the flat portion 26, and the periphery of the substrate support convex portion 27. And a recessed groove portion 28 provided in the. The substrate support convex portions 27 are formed in a columnar shape having a substrate mounting portion 27a at the upper end, and are provided at four locations at equal intervals in the circumferential direction of the outer peripheral portion of the circular planar portion 26. The depth of the substrate holding recess 23 and the height of the substrate support convex portion 27 are determined between the back surface of the substrate 22 and the flat portion 26 when the substrate 22 is placed on the substrate placement portion 27 a of the substrate support convex portion 27. In addition, a sufficient distance is formed to prevent contact heat conduction, and the upper surface of the substrate 22, the upper surface of the rotating member 13, the upper surface of the substrate holding member 20, and the upper surface of the cover member 25 are set to be flush with each other. ing.

  The diameter and height of the substrate support convex portion 27 formed in a columnar shape vary depending on conditions such as the material and diameter of the substrate 22 and the substrate heating temperature during thin film growth, but usually the diameter is 1 to 5 mm, preferably 3 mm. The height is about 50 to 200 μm, preferably about 100 μm. The number of the substrate support protrusions 27 is only required to be able to support the substrate 22 in a stable state, and is usually 3 to 6, preferably about 4. Furthermore, the contact heat conduction area can be further reduced by reducing the diameter of the substrate support convex portion 27, but there is a risk that processing is difficult or damage is caused during use.

  The opening width and depth of the concave groove 28 are set to optimum dimensions according to conditions such as the diameter and height of the substrate supporting convex portion 27, the material and diameter of the substrate 22, and the substrate heating temperature. When the diameter of the supporting convex portion 27 is 3 mm and the height is 100 μm, both the opening width and depth are optimally about 1 mm. If the opening width and depth of the concave groove portion 28 are too small, it is difficult to sufficiently exert the effect of providing the concave groove portion 28, and the concave groove portion 28 is provided even if the opening width and depth are excessively increased. The effect cannot be fully exhibited.

  When a thin film is formed on the surface of the substrate 22 using this vapor phase growth apparatus, the substrate 22 is placed on the substrate supporting convex portion 27 and the substrate 22 is held in the substrate holding concave portion 23, and the heater 16, while heating the substrate 22 to a preset temperature via the rotating member 13 and the substrate holding member 20, the raw material gas is introduced into the chamber 11 from the gas introduction unit 14, and the exhaust gas is introduced into the chamber through the gas discharge unit 15. 11 is discharged from the inside. At this time, by rotating and driving the rotating member 13 by the rotating shaft 12, the substrate holding member 20 revolves around the rotating shaft 12, and the external gear 20a of the substrate holding member 20 meshes with the internal gear 24a and the substrate holding member. As the substrate 20 rotates, the substrate 22 held by the substrate holding member 20 is rotated and revolved in the chamber 11.

  The substrate holding member 20 at the time of heating the substrate is at a temperature higher than the set temperature of the substrate 22, and most of the substrate 22 excluding a portion in contact with the substrate support convex portion 27 and a portion facing the concave groove portion 28. Is uniformly heated by radiant heat conduction from the flat portion 26. On the other hand, the substrate back surface portion placed on the substrate support convex portion 27 is heated by contact heat conduction from the substrate placement portion 27 a and faces the concave groove portion 28 provided around the substrate support convex portion 27. The portion is heated by radiant heat conduction from the bottom surface of the groove 28.

  Therefore, the heating amount of the substrate back surface portion heated by the contact heat conduction from the substrate mounting portion 27a is larger than the heating amount of the substrate back surface heated by the radiant heat conduction from the flat surface portion 26. The amount of heating by radiant heat conduction of the substrate back surface portion facing the recessed groove portion 28 where the distance between the back surface and the bottom surface of the recessed groove portion 28 is separated from the distance between the back surface of the substrate 22 and the flat surface portion 26 is Less.

  For this reason, on the back surface of the substrate 22, the temperature of the portion of the substrate support convex portion 27 in contact with the substrate mounting portion 27 a is higher than the temperature of the portion facing the flat portion 26 of the substrate holding recess 23, and the groove portion However, since the high temperature portion and the low temperature portion are adjacent to each other, heat conduction occurs inside the substrate 22 and the temperature in contact with the substrate mounting portion 27a. The thermal energy moves from the high part to the low temperature part facing the concave groove part 28.

  As a result, the temperature of the portion in contact with the substrate mounting portion 27a decreases, the temperature of the portion facing the concave groove portion 28 increases, and the temperature of the portion in contact with the substrate mounting portion 27a on the surface of the substrate 22 The temperature of the portion facing the concave groove portion 28 is averaged, and both temperatures approach the temperature of the portion facing the flat portion 26. That is, by providing the concave groove portion 28 around the substrate supporting convex portion 27 and setting these shapes and dimensions optimally, the in-plane temperature distribution on the surface of the substrate 22 can be eliminated, and the surface of the substrate 22 can be eliminated. The in-plane uniformity of the thin film to be formed can be improved, and the yield can be improved.

  4 and 5 show a second embodiment of the present invention. In the following description, the same reference numerals are given to the same components as those of the vapor phase growth apparatus shown in the first embodiment. Detailed description will be omitted.

  In this embodiment, the substrate support convex portions 31 are provided at four locations at equal intervals in the circumferential direction on the outer peripheral portion of the flat portion 26 in the substrate holding concave portion 23, and the concave groove portion that is continuous in a ring shape on the outer peripheral edge of the flat portion 26 32 is formed. Thus, by forming the concave groove 32 on the outer peripheral edge of the flat portion 26, the temperature of the portion where the temperature is increased by the contact heat conduction from the substrate supporting convex portion 31 can be lowered, and the surface of the substrate 22 can be reduced. It is possible to eliminate the in-plane temperature distribution at.

  6 and 7 show a second embodiment of the present invention. In this embodiment, a substrate support convex portion 41 that is continuous in a ring shape is provided on the outer peripheral portion of the flat portion 26 in the substrate holding recess 23. The concave groove portion 42 is formed in a ring shape adjacent to the outer periphery of the substrate support convex portion 41. Thus, by forming the substrate support convex portion 41 and the concave groove portion 42 in a ring shape, the temperature of the portion where the temperature is increased by contact heat conduction from the substrate support convex portion 31 can be lowered. It is possible to eliminate the in-plane temperature distribution on the surface.

  In addition, the cross-sectional shape of each concave groove part is not restricted to a tetragon | quadrangle, A V-shaped and U-shaped groove | channel may be sufficient. Further, in the second embodiment and the third embodiment, the groove portion can be formed adjacent to the substrate support protrusion. Also, the plurality of concave grooves can be provided in double or triple, and can be formed in an arc shape without being continuous in a ring shape. Furthermore, the substrate mounting portion and the groove portion of the substrate supporting convex portion need not be circular in plan view, and may be polygonal, or the substrate mounting portion may be spherical. In each embodiment, the rotation member and the substrate holding member are separately formed in a self-revolution type vapor phase growth apparatus. However, in the vapor growth apparatus for only rotation or only rotation, the substrate The holding member and the rotating member may be integrated, or the substrate may not be rotated.

  DESCRIPTION OF SYMBOLS 11 ... Chamber, 12 ... Rotating shaft, 13 ... Rotating member, 13a ... Housing recessed part, 14 ... Gas introduction part, 15 ... Gas discharge part, 16 ... Heater, 17 ... Thermometer, 18 ... Reflector, 19 ... Rolling member, 19a, 19b ... rolling groove, 20 ... substrate holding member, 20a ... external gear, 21 ... guide member, 22 ... substrate, 23 ... substrate holding recess, 24 ... fixed gear member, 24a ... internal gear, 25 ... cover material, 26 ... Planar part, 27 ... Substrate support convex part, 27a ... Substrate mounting part, 28 ... Concave groove part, 31, 41 ... Substrate support convex part, 32, 42 ... Concave groove part

Claims (3)

  A substrate is held in a substrate holding recess provided in the substrate holding member, the substrate is heated via the substrate holding member heated by a heating means, and a source gas is supplied onto the substrate to supply the substrate surface. In the vapor phase growth apparatus for forming a thin film, the substrate holding recess includes a flat portion parallel to the back surface of the substrate, and a substrate support protrusion protruding upward from the flat portion and provided with a substrate mounting portion at the upper end. A vapor phase growth apparatus comprising: a groove portion provided in the planar portion adjacent to the substrate supporting convex portion.   The vapor phase growth apparatus according to claim 1, wherein the substrate support convex portion is formed in a cylindrical shape.   3. The vapor phase growth apparatus according to claim 2, wherein the concave groove portion is provided in a ring shape around the cylindrical substrate support convex portion.

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