A Ga 2O 3 passivation technique compatible with GaAs device processing

Abstract

Electronic and structural properties of ex-situ fabricated Ga 2O 3GaAs interfaces have been investigated. The fabrication comprises thermal desorption of native oxide and subsequent Ga 2O 3 film deposition on (100) GaAs wafers in ultra-high vacuum. Interfacial x-ray photoelectron spectroscopy revealed the absence of As x O y indicating thermodynamic stability of the oxide-GaAs interface. A low interface recombination velocity S of 9000 cm/s equivalent to an interface state density D it in the upper 10 10 cm −2 eV −1 range has been inferred. The technique provides excellent passivation for GaAs wafers or surfaces exposed to room air and/or processing environments during fabrication of devices such as FETs, HBTs, etc.