Silicon carbide single crystal substrate

A silicon carbide single crystal substrate comprising a main surface inclined in a <11-20> direction relative to a (0001) plane, wherein

• when a detector is positioned in a [11-20] direction when viewed in a direction perpendicular to the main surface, a first measurement region including a center of the main surface is irradiated with an X ray in a direction within ±15° relative to a [-1-120] direction, and a diffracted X ray from the first measurement region is measured using the detector, a ratio of a maximum intensity of a first intensity profile of the diffracted X ray in a range of 6.9 keV to 11.7 keV to a background intensity of the first intensity profile being more than or equal to 1500, and
• when the detector is positioned in a direction parallel to a [-1100] direction when viewed in the direction perpendicular to the main surface, the first measurement region is irradiated with an X ray in a direction within ±6° relative to a [1-100] direction, and a diffracted X ray from the first measurement region is measured using the detector, a ratio of a maximum intensity of a second intensity profile of the diffracted X ray in a range of 8.0 keV to 9.5 keV to a background intensity of the second intensity profile being more than or equal to 1500, and
• when the detector is positioned in the [11-20] direction when viewed in the direction perpendicular to the main surface and a location to be irradiated with the X ray is changed in a range of ±15° relative to the [-1-120] direction, an absolute value of a difference between maximum value and minimum value of energy at which the first intensity profile indicates a maximum value in the range of 6.9 keV to 11.7 keV being less than or equal to 0.06 keV.