Demonstration of a 2 kV Al<sub>0.85</sub>Ga<sub>0.15</sub>N Schottky Barrier Diode With Improved On-Current and Ideality Factor
Yanni Zhang, Jincheng Zhang, Zhihong Liu, Shengrui Xu, Kai Cheng, Jing Ning, Chunfu Zhang, Lei Zhang, Peijun Ma, Hong Zhou, Yue Hao
Abstract
In this letter, we report on demonstrating a Schottky barrier diode (SBD) with high reverse blocking voltage by incorporating an ultra-wide bandgap semiconductor Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.85</sub> Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15</sub> N channel. Benefited from the lower activation energy of the Si in GaN, the net carrier concentration of Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.85</sub> Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15</sub> N can be essentially enhanced to 2 × cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> level with surface roughness of 0.33 nm. Due to the good material property, a reverse blocking voltage of 2 kV and room temperature ideality factor of 2.3 are demonstrated. Combined with the significantly improved on-current and on/off ratio of more than 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> when compared with other AlN SBDs, Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.85</sub> Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15</sub> N turns out to be a competitive AlN counterpart by considering the compromise among ultra-wide bandgap, dopant activation, and material property.