Annealing Pressure and Ambient Dependent RuO_xSchottky Contacts on InAlN/AlN/GaN-on-Si(111) Heterostructure

Abstract

We report the annealing pressure and ambient (vacuum at the pressure of 6.67 × 10−3 Pa, N2 and Ar at the pressure of 101.3 kPa) dependent electrical and material characteristics of RuOx Schottky contacts on InAlN/AlN/GaN-on-Si(111) heterostructures. With respect to RuOx Schottky contacts without annealing, those annealed in vacuum at 800°C for 1 minute have ∼0.208 eV reduced effective Schottky Barrier Height (SBH) and about one order of magnitude increased reverse leakage current. In contrast, RuOx Schottky contacts annealed in Ar have ∼0.207 eV increased SBH and about 100 times reduced reverse leakage current decreases. RuOx Schottky contacts annealed in N2 yields similar electrical and material characteristics to those annealed in Ar(an inert ambient). This indicates that N2 is unlikely to react with RuOx and the annealing pressure probably plays a critical role in changing the electrical and material characteristics of RuOx Schottky diodes.