Abstract: A structural body includes a sapphire underlying substrate; and a semiconductor layer of a group III nitride semiconductor disposed on the underlying substrate. An upper surface of the underlying substrate is a crystal surface tilted at an angle of 0.5° or larger and 4° or smaller with respect to a normal line of an a-plane which is orthogonal to an m-plane and belongs to a {11-20} plane group, from the m-plane which belongs to a {1-100} plane group.

Abstract: A method for manufacturing a semiconductor device includes the steps of: (a) preparing a non-polar single crystal substrate; (b) epitaxially growing an MgO layer on the non-polar single crystal substrate to a thickness of 3 nm or thicker to have rocksalt structure at a substrate temperature of 500° C. to 800° C.; (c) growing on the MgO layer a low temperature growth layer made of ZnO group material at a substrate temperature of 500° C. or lower; (d) annealing the low temperature growth layer above the substrate at a temperature of 700° C. or higher; and (e) epitaxially growing a high temperature growth layer of ZnO group material on the annealed low temperature growth layer at a temperature of 600° C. or higher.

Abstract: A method for manufacturing a semiconductor device includes the steps of: (a) preparing a non-polar single crystal substrate; (b) epitaxially growing an MgO layer on the non-polar single crystal substrate to a thickness of 3 nm or thicker to have rocksalt structure at a substrate temperature of 500° C. to 800° C.; (c) growing on the MgO layer a low temrperature growth layer made of ZnO group material at a substrate temperature of 500° C. or lower; (d) annealing the low temperature growth layer above the substrate at a temperature of 700° C. or higher; and (e) epitaxially growing a high temperature growth layer of ZnO group material on the annealed low temperature growth layer at a temperature of 600° C. or higher.