A method for simultaneously manufacturing more than one single crystal of a semiconductor material by physical vapor transport (PVT) includes connecting a pair of reactors to a vacuum pump system by a common vacuum channel and creating and/or controlling, with the vacuum pump system, a common gas phase condition in the inner chambers of the pair of reactors. Each reactor has an inner chamber adapted to accommodate a PVT growth structure for growth of a semiconductor single crystal.

A method for simultaneously manufacturing more than one single crystal of a semiconductor material by physical vapor transport (PVT) includes connecting a pair of reactors to a vacuum pump system by a common vacuum channel and creating and/or controlling, with the vacuum pump system, a common gas phase condition in the inner chambers of the pair of reactors. Each reactor has an inner chamber adapted to accommodate a PVT growth structure for growth of a semiconductor single crystal.

A buffer layer on a silicon carbide substrate and a method of forming the same are disclosed. The buffer layer includes at least two layers of silicon carbide films, in which at least each lower one is doped at a top surface thereof with predetermined ions. As a result, at the top surface of the silicon carbide film, a barrier with different parameter is formed, which can block dislocation defects that have spread into the silicon carbide film from further upward propagation in the silicon carbide film.

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.

The disclosure provides a silicon carbide seed crystal and a method of manufacturing a silicon carbide ingot. The silicon carbide seed crystal has a silicon surface and a carbon surface opposite to the silicon surface. A difference D between a basal plane dislocation density BPD1 of the silicon surface and a basal plane dislocation density BPD2 of the carbon surface satisfies the following formula (1), a local thickness variation (LTV) of the silicon carbide seed crystal is 2.5 μm or less, and a stacking fault (SF) density of the silicon carbide seed crystal is 10 EA/cm.sup.2 or less:

D=(BPD1−BPD2)/BPD1≤25%  (1).

The disclosure provides a silicon carbide seed crystal and a method of manufacturing a silicon carbide ingot. The silicon carbide seed crystal has a silicon surface and a carbon surface opposite to the silicon surface. A difference D between a basal plane dislocation density BPD1 of the silicon surface and a basal plane dislocation density BPD2 of the carbon surface satisfies the following formula (1), a local thickness variation (LTV) of the silicon carbide seed crystal is 2.5 μm or less, and a stacking fault (SF) density of the silicon carbide seed crystal is 10 EA/cm.sup.2 or less:

D=(BPD1−BPD2)/BPD1≤25%  (1).

A SiC ingot includes a seed crystal and a single crystal grown on the seed crystal, wherein the single crystal has therein a micropipe passing through the single crystal in a growth direction, and when photoluminescence observation is performed on a plurality of wafers cut out from the single crystal in a direction intersecting the growth direction, an S/N ratio of the micropipe in a first wafer cut out of the plurality of wafers, which is closest to the seed crystal, is higher than an S/N ratio of the micropipe in a second wafer cut out from a position further away from the seed crystal than the first wafer.

A SiC ingot includes a seed crystal and a single crystal grown on the seed crystal, wherein the single crystal has therein a micropipe passing through the single crystal in a growth direction, and when photoluminescence observation is performed on a plurality of wafers cut out from the single crystal in a direction intersecting the growth direction, an S/N ratio of the micropipe in a first wafer cut out of the plurality of wafers, which is closest to the seed crystal, is higher than an S/N ratio of the micropipe in a second wafer cut out from a position further away from the seed crystal than the first wafer.

A rare earth-containing SiC substrate includes a rare earth element and Al. A concentration of the rare earth element is from 1×10.sup.16 atoms/cm.sup.3 to 1×10.sup.19 atoms/cm.sup.3 inclusive and a concentration of Al is from 1×10.sup.16 atoms/cm.sup.3 to 1×10.sup.21 atoms/cm.sup.3 inclusive.