Silicon carbide epitaxial substrate having grooves extending along main surface and method of manufacturing silicon carbide semiconductor device

A silicon carbide epitaxial substrate comprising:

• a silicon carbide single-crystal substrate including a first main surface;
• and
• a silicon carbide layer on the first main surface,
• the silicon carbide layer including a second main surface opposite to a surface thereof in contact with the silicon carbide single-crystal substrate,
• an average value of carrier concentration in the silicon carbide layer being not less than 1×1015 cm−3 and not more than 5×1016 cm−3,
• in-plane uniformity of the carrier concentration being not more than 2%,
• the second main surface having
• grooves extending in one direction along the second main surface, a width of each of the grooves in the one direction being twice or more as large as a width thereof in a direction perpendicular to the one direction, and a maximum depth of each of the grooves from the second main surface being not more than 10 nm, and
• one or more carrot defects,
• a value obtained by dividing a number of the one or more carrot defects by a number of the grooves being not more than 1/500,
• the silicon carbide single-crystal substrate having a diameter of not less than 150 mm.