Editors : C. L. Briant, W. A. T. Clark, U. Dahmen
a1 Department of Electrical Engineering, University of Pittsburgh, Pittsburgh, PA 15261
Sputter deposition of ZnO films on GaAs substrates has been investigated. ZnO Alms were deposited using a ZnO compound target in Ar or Ar/O2 (95/5) ambient. Deposition parameters such as RF power, substrate-target distance, and gas composition/pressure were optimized to obtain highly c-axis oriented and highly resistive films. Deposited films were characterized by X-ray diffraction, scanning electron microscopy, capacitance, resistivity, and breakdown field strength measurements. X-ray diffraction measurements show a strong (0002)-plane peak with a full-width-half-maximum of less than 1°, indicating that the ZnO films deposited on GaAs substrates are highly c-axis oriented. DC resistivities of the films were measured to be on the order of 1011 Ω-cm.