GAN EPITAXIAL-GROWTH ON NEODIUM GALLATE SUBSTRATES

We have investigated the feasibility of neodium gallate (NdGaO3, NGO) as substrates for GaN epitaxial growth for the first time. GaN films d eposited on neodium gallate substrates by the hydride vapor phase epit axy technique have been found to be single-crystalline with the epitax ial relationship of GaN(0001)/NGO(011) and GaN[<10(1)over bar 0>]paral lel to NGO[100], where the lattice mismatch between the film and the s ubstrate is less than 2%. Photoluminescence (PL) of GaN/NGO films at r oom temperature showed a strong band edge emission with little emissio n in the longer wavelength region. The carrier concentration and the e lectronmobility of GaN/NGO films were 7 x 10(19) cm(-3) and 45 cm(2)/V s, respectively. These results are superior to those of GaN/sapphire f ilms deposited simultaneously under the same conditions. (C) 1997 Else vier Science Ltd.