Characteristics of AlN layer on four-inch sapphire substrate by high-temperature annealing in nitrogen atmosphere

In this study, we developed an annealing furnace for 4 inch wafers and used it to anneal AlN on a 4 inch c-plane sapphire substrate at 1700°C for 1 h in a pure N2 atmosphere by using the annealing furnace (STA1800, Taiyo Nippon Sanso). FWHM of the XRC of the (0002) of 48.6 arcsec, and that of the (10-12) of 278.2 arcsec was obtained.