III-NITRIDE SEMICONDUCTOR GROWTH SUBSTRATE, III-NITRIDE SEMICONDUCTOR EPITAXIAL SUBSTRATE, III-NITRIDE SEMICONDUCTOR ELEMENT, III-NITRIDE SEMICONDUCTOR FREESTANDING SUBSTRATE, AND METHOD FOR FABRICATING THESE

摘要

Disclosed are a III-nitride semiconductor epitaxial substrate, a III-nitride semiconductor element, and a III-nitride semiconductor freestanding substrate, which have good crystallinity, not only with AlGaN, GaN, or GaInN, the growth temperature of which is at or below 1050°C, but also with AlxGa1-xN, the growth temperature of which is high and which has a high Al composition, a III-nitride semiconductor growth substrate for fabricating these, and a method to efficiently fabricate these, which is characterized by being equipped with a crystal growth substrate, at least the surface portion of which is made from a III-nitride semiconductor containing Al, and a single metallic layer that is made from Zr or Hf and is formed on the aforementioned surface portion.