CRYSTAL LAYERED STRUCTURE AND METHOD FOR MANUFACTURING SAME, AND SEMICONDUCTOR ELEMENT

摘要

Provided is a crystal layered structure having a low dislocation density on the upper surface of a nitride semiconductor layer on a Ga 2 O 3 substrate, and a method for manufacturing the same. In one embodiment, there is provided a crystal layered structure (11) including: a Ga 2 O 3 substrate (12); a buffer layer (13) comprising an Al x Ga y In z N (0 ‰¤ x ‰¤ 1, 0 ‰¤ y ‰¤ 1, 0 ‰¤ z ‰¤ 1, x + y + z = 1) crystal on the Ga 2 O 3 substrate (12); and a nitride semiconductor layer (14) comprising an Al x Ga y In z N (0 ‰¤ x ‰¤ 1, 0 ‰¤ y ‰¤ 1, 0‰¤ z ‰¤ 1, x + y + z = 1) crystal including oxygen as an impurity on the buffer layer (13). The oxygen concentration in a region (14a) having a thickness of no less than 200 nm on the nitride semiconductor layer (14) on the side towards the Ga 2 O 3 substrate (12) is no less than 1.0x10 18 /cm 3 .