Ga2O3 THIN FILM DEPOSITED BY ATOMIC LAYER DEPOSITION WITH HIGH PLASMA POWER

Abstract

Ga2O3 thin films were deposited at 200°C on p-type Si (100) by plasma-enhanced atomic layer deposition technique with an alternating supply of reactant source, [(CH3)2GaNH2]3, and high-power oxygen plasma of 180 W. The as-deposited thin films were annealed at 500, 700, 900°C in oxygen ambient for 10 min in a rapid thermal annealing system, respectively. X-ray diffractometer and atomic force microscope were used to investigate the structural properties and the surface morphologies of the thin films. The as-deposited thin film was amorphous and the thin films annealed at high temperatures were monoclinic β -phase Ga2O3. The electrical properties of Pt/Ga2O3/Si structured thin film were investigated using a semiconductor parameter analyzer. It was found that the as-deposited thin film and the thin film annealed at 500°C were leaky, however, the insulating properties of the thin films annealed at high temperatures were greatly improved. Spectroscopic ellipsometry was also used to derive the refractive indices and the thicknesses of the thin films.