Semi-insulating compound semiconductor substrate and semi-insulating compound semiconductor single crystal

The invention relates to a semi-insulating compound semiconductor substrate and a semi-insulating compound semiconductor single crystal. A semi-insulating compound semiconductor substrate includes a semi-insulating compound semiconductor, the semi-insulating compound semiconductor substrate being configured such that, on a main surface having a (100) plane orientation, at least one of a first surface and a second surface is formed along a tilt direction from a center of the main surface, and a tilt direction along a tilt direction from a center of the main surface. 110gt, 110gt; a standard deviation/average value of specific resistance measured at an interval of 0.1 mm in four equivalent directions of the directions and lt from the center of the main surface; 100 gt; the standard deviation/average value of the specific resistance measured at an interval of 0.1 mm in each of four equivalent directions of the directions is 0.1 or less. 本发明涉及半绝缘性化合物半导体基板和半绝缘性化合物半导体单晶。一种半绝缘性化合物半导体基板，其包含半绝缘性化合物半导体，所述半绝缘性化合物半导体基板被构