Laminate substrate, freestanding substrate, method for manufacturing laminate substrate, and method for manufacturing freestanding substrate

Abstract

A laminate substrate which includes a single crystal diamond (111) layer, including: an underlying substrate, an intermediate layer on the underlying substrate, and the single crystal diamond (111) layer on the intermediate layer, in which the underlying substrate has a main surface which has an off angle within a range, −8.0° or more and −0.5° or less, or +0.5° or more and +8.0° or less in a crystal axis [_1_1 2] direction or a threefold symmetry direction thereof relative to a crystal plane orientation of (111), and the single crystal diamond (111) layer has an off angle within a range, more than −10.5° and less than −2.0°, or more than +2.0° and less than +10.5° in the crystal axis [_1_1 2] direction or a threefold symmetry direction thereof relative to the crystal plane orientation of (111).