Crystal Orientation and Electrical Properties of Al and Ga Co-Doped Zinc Oxide Transparent Conducting Films Deposited on Sapphire Surface

Abstract

Transparent conducting films of zinc oxide co-doped with aluminum and gallium (AGZO) were deposited on sapphire (single crystal of aluminum oxide) substrates by spray chemical vapor deposition. The AGZO films were epitaxial or with strongly preferred-orientation. The highest mobility was 48 cm2 V-1 s-1 when deposited on r-plane. Deposition on other surfaces doubled the mobility to approximately 30 cm2 V-1 s-1 than that on glass substrate. Resistivity of all films deposited on sapphire substrate were lower than 1.0×10-3 ·cm and lower than that (2.4×10-3 ·cm) deposited on glass substrate. The lowest resistivity was 5.8×10-4 ·cm when deposited on c-plane.