Effects of thermal oxidation interfacial layer on the photoelectrical properties of GaN-based Schottky diodes

摘要

Thermal oxidation interfacial layer was inserted into the GaN-based material and Schottky contact interface during the device preparation to increase the barrier height. Different thickness of thermal oxidation interfacial layer was created by keeping the chips in the Rapid Thermal Processor (RTP) in atmosphere ambient for different periods of time before evaporating transparent Schottky contact. For GaN Schottky diodes, as the time kept in RTP increases, the diodes' zero-bias resistances decrease and the dark current increase considerably, and the peak photoresponse and UV-visible rejection factor of the responsivity of the diodes decrease abruptly. For Al_(0.45)Ga_(0.55)N Schottky diodes, as the time increase, the diodes' zero-bias resistances and dark current increase slightly, while the peak photoresponse and the UV/visible rejection factor of the responsivity of the diodes decrease a little.