The optimized interface characteristics of β-Ga_2O_3 Schottky barrier diode with low temperature annealing

摘要

A low temperature controlled annealing technique was utilized to improve the performance of vertical β-gallium oxide (β-Ga_2O_3) Schottky barrier diodes (SBDs) in this work. The nickel is diffused into Ga_2O_3, and NiO was formed at the interface between the anode and semiconductor generating p-n junction after low temperature annealing. Simultaneously, the trap state density of interface Ni/Ga_2O_3 as well as the carbon bonded with oxygen on the surface was reduced, which was proved by the capacitance and conductance measurements and x-ray photoelectron spectroscopic analysis, respectively. Combined the decreased saturation current density by three orders of magnitude from 1.21 × 10~(-6) to 9.27 × 10~(-8) and 5.12 × 10~(-9) A/cm~2 and larger breakdown voltage from 220 to 270 V owing to the optimized interface and the formation of NiO, a low temperature annealing technique makes certain effective improvement for vertical β-Ga_2O_3 SBDs via interface engineering.