Performance Enhancement of n-Type AlN Schottky Barrier Diodes Using Oxygen-Rich Rapid Thermal Annealing Treatment

Abstract

In this letter, we present a high-performance aluminum nitride (AlN) lateral Schottky barrier diode (SBD) achieved through rapid thermal annealing (RTA) in an oxygen environment. This treatment dramatically reduces the reverse leakage current and significantly enhances the Schottky contact performance. These treated SBDs exhibit impressive room temperature (RT) characteristics, including a rectification ratio of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 10^{{7}}$ </tex-math></inline-formula>, an ideality factor of 2.04, a barrier height of 1.84 eV, and the highest breakdown voltages at the kilovolt level. Even under elevated temperatures, these devices maintain exceptional stability, showcasing their robust performance. This notable enhancement results from effective defect compensation, reducing defect-assisted tunneling paths. X-ray photoelectron spectroscopy (XPS) and capacitance-voltage analysis confirm the presence of an oxygen diffusion layer near the AlN surface posttreatment, further contributing to enhanced defect compensation. This work marks a significant milestone in advancing AlN SBDs, offering the potential for more efficient and reliable devices in high-power applications.