Field-induced current modulation in epitaxial film of deep-ultraviolet transparent oxide semiconductor Ga2O3

Abstract

Epitaxial films of a deep-ultraviolet transparent oxide semiconductor, Ga2O3, were fabricated on α-Al2O3 (0001) substrates by pulsed laser deposition. Four-axes x-ray diffraction measurements revealed that the tin-doped Ga2O3 films have a crystal structure different from any known polymorphs of Ga2O3. Its crystal lattice was determined to be an orthorhombic. Top gate field-effect transistor structures were fabricated using the Ga2O3 epitaxial films for n-channels. The channel conductance was modulated by an order of magnitude by gate voltage at room temperature with an estimated field-effect mobility of 5×10−2cm2(Vs)−1.