A gallium nitride vapor phase epitaxy apparatus capable of doping magnesium is provided. The apparatus is used in vapor phase epitaxy not using organic metal as a gallium raw material. The apparatus comprises a reactor vessel and a wafer holder. The apparatus comprises a first raw material gas supply pipe configured to supply a first raw material gas containing gallium. The apparatus comprises a second raw material gas supply pipe configured to supply a second raw material gas, which contains nitrogen and configured to react with the first raw material gas. The apparatus comprises a third raw material gas supply pipe configured to supply a third raw material gas containing magnesium. The third raw material gas supply pipe is configured capable of placing a magnesium-based oxide on its supply path. The apparatus comprises a first heating unit configured to heat the magnesium-based oxide in a first temperature range.

A gallium nitride vapor phase epitaxy apparatus capable of doping magnesium is provided. The apparatus is used in vapor phase epitaxy not using organic metal as a gallium raw material. The apparatus comprises a reactor vessel and a wafer holder. The apparatus comprises a first raw material gas supply pipe configured to supply a first raw material gas containing gallium. The apparatus comprises a second raw material gas supply pipe configured to supply a second raw material gas, which contains nitrogen and configured to react with the first raw material gas. The apparatus comprises a third raw material gas supply pipe configured to supply a third raw material gas containing magnesium. The third raw material gas supply pipe is configured capable of placing a magnesium-based oxide on its supply path. The apparatus comprises a first heating unit configured to heat the magnesium-based oxide in a first temperature range.

A CVD apparatus for manufacturing a III-nitride-based layer having a rotating wafer carrier positioned inside a reaction chamber that receives a mixture of a nitrogen gas source and a group III element gas source. Recesses are formed within the wafer carrier, each including a satellite disc of thickness x for accepting a wafer of thickness t. The satellite disc includes a peripheral notch of height a, and a notch thickness of x−a=b. A peripheral retaining ring includes a vertical rise portion extending a distance of e+f and a laterally-extending portion, the laterally-extending portion engaging the satellite disc notch. A gap c is formed between the substrate and a surface of the satellite disc. The relationship of a+b+c+t=b+e+f is satisfied such that laminar flow occurs in the region of the retaining ring.

A preheat ring (126) for use in a chemical vapor deposition system includes a first portion and a second portion selectively coupled to the first portion such that the first and second portions combine to form an opening configured to receive a susceptor therein. Each of the first and second portions is independently moveable with respect to each other.

A preheat ring (126) for use in a chemical vapor deposition system includes a first portion and a second portion selectively coupled to the first portion such that the first and second portions combine to form an opening configured to receive a susceptor therein. Each of the first and second portions is independently moveable with respect to each other.

Provided is a susceptor which makes it possible to increase the circumferential flatness uniformity of an epitaxial layer of an epitaxial silicon wafer. A susceptor 100 is provided with a concave counterbore portion on which a silicon wafer W is placed, and the radial distance L between the center of the susceptor and an opening edge of the counterbore portion varies at 90° periods in the circumferential direction. Meanwhile, when the angle at which the radial distance L is minimum is 0°, the radial distance L is a minimum value L.sub.1 at 90°, 180°, and 270°; and the radial distance L is a maximum value L.sub.2 at 45°, 135°, 225°, and 315°. Accordingly, the pocket width L.sub.p also varies in conformance with the variations of the radial distance L. The opening edge 110C describes four elliptical arcs being convex radially outward when the susceptor 100 is viewed from above.

Provided is a susceptor which makes it possible to increase the circumferential flatness uniformity of an epitaxial layer of an epitaxial silicon wafer. A susceptor 100 is provided with a concave counterbore portion on which a silicon wafer W is placed, and the radial distance L between the center of the susceptor and an opening edge of the counterbore portion varies at 90° periods in the circumferential direction. Meanwhile, when the angle at which the radial distance L is minimum is 0°, the radial distance L is a minimum value L.sub.1 at 90°, 180°, and 270°; and the radial distance L is a maximum value L.sub.2 at 45°, 135°, 225°, and 315°. Accordingly, the pocket width L.sub.p also varies in conformance with the variations of the radial distance L. The opening edge 110C describes four elliptical arcs being convex radially outward when the susceptor 100 is viewed from above.

Provided are an epitaxial wafer growth furnace, an apparatus, an MOCVD method, and an epitaxial wafer. The growth furnace comprises: a growth furnace body for placing a substrate, an upper end face of the growth furnace body is a downward concave spherical surface, and the upper end face of the spherical shape has a preset mark position; when the substrate is placed on the preset mark position and the growth furnace body rotates, a difference value of the centrifugal force applied to each part of the substrate is within a preset range. The growth furnace body is a downward concave spherical surface, such that the substrate can be placed at the position where the centrifugal force applied to each part of the substrate is equal or similar, and thus each part on the substrate has same growth stress, the epitaxial wafer with a uniform thickness is obtained.

Provided are an epitaxial wafer growth furnace, an apparatus, an MOCVD method, and an epitaxial wafer. The growth furnace comprises: a growth furnace body for placing a substrate, an upper end face of the growth furnace body is a downward concave spherical surface, and the upper end face of the spherical shape has a preset mark position; when the substrate is placed on the preset mark position and the growth furnace body rotates, a difference value of the centrifugal force applied to each part of the substrate is within a preset range. The growth furnace body is a downward concave spherical surface, such that the substrate can be placed at the position where the centrifugal force applied to each part of the substrate is equal or similar, and thus each part on the substrate has same growth stress, the epitaxial wafer with a uniform thickness is obtained.

The substrate is doped with P, has a resistivity adjusted to 1.05 mΩ.Math.cm or less, and includes defects, formed in the crystal by the aggregation of P, which are Si—P crystal defects substantially. The method includes a step of forming a silicon oxide film on the backside of the substrate with a thickness of 300 nm or more and 700 nm or less, a step of mirror-polishing the substrate, and after the mirror-polishing step, a heat treatment step of the substrate mounted on a substrate holder made of Si or SiC, on the holder surface a silicon oxide film is formed with the thickness between 200 nm and 500 nm, wherein the thickness X of the silicon oxide film of the holder and the thickness Y of that on the backside of the substrate satisfy a relational expression Y=C−X, where C is a constant between 800 and 1000.