Direct heteroepitaxial growth of ZnO over GaN crystal in aqueous solution

Abstract

We report on the structural and electrical properties of ZnO films grown on surface-treated GaN/Al2O3substrates by chemical bath deposition. X-ray diffraction analysis indicated that the ZnO films had a single-crystalline wurtzite structure with c-axis orientation. The ZnO film exhibited n-type conduction with a carrier concentration of 6.9×m-3, an electron mobility of 41 cm2/(Vs), and a resistivity of 2.2× 10-2 Ωcm. A low specific contact resistivity of 4.3 × 10-3Ωcm2 was obtained at the ZnO/n-GaN interface. Additionally, the ZnO film exhibited high transparency in the visible and infrared region. © 2013 The Japan Society of Applied Physics.