Silicon carbide single crystal substrate, silicon carbide epitaxial substrate, and method of manufacturing silicon carbide semiconductor device

A silicon carbide single crystal substrate comprising:

• a first main surface;
• and
• an orientation flat extending in a <11-20> direction,
• the first main surface including an end region extending by at most 5 mm from an outer periphery of the first main surface, and
• in a direction perpendicular to the first main surface, an amount of warpage of the end region continuous to the orientation flat being not greater than 3 μm,
• a conductivity type of the silicon carbide single crystal being n type,
• the first main surface being a surface inclined by an angle from a {0001} plane, the angle being not smaller than 1° and not greater than 8°.