METHODS FOR PRODUCING SINGLE CRYSTAL SUBSTRATE, NH-SILICON CARBIDE SUBSTRATE AND 4H-SILICON CARBIDE SINGLE CRYSTAL SUBSTRATE, AND 4H-SILICON CARBIDE SINGLE CRYSTAL SUBSTRATE, AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a single crystal substrate having a composite step-terrace structure comprising a downward step and an upward step on the surface of a single crystal.SOLUTION: The method for producing the single crystal substrate, which has the composite step-terrace structure comprising a first flat terrace, a first downward step, a second flat terrace and a second upward step having the height lower than that of the first downward step, comprises a step to etch an original single crystal substrate to form the composite step-terrace structure in a self-organizing manner.