Improved device performance of vertical GaN-on-GaN nanorod Schottky barrier diodes with wet-etching process
Yaqiang Liao, Tao Chen, Jia Wang, Wentao Cai, Yuto Ando, Xu Yang, Hirotaka Watanabe, Atsushi Tanaka, Shugo Nitta, Yoshio Honda, Kevin J. Chen, Hiroshi Amano
Abstract
In this work, a deliberate etching-based top-down approach is proposed to fabricate the GaN nanorod (NR) Schottky barrier diode (SBD). As a key step during the fabrication, the impact of the wet-etching process on device performance is systematically studied. By virtue of the reduced surface states at the sidewall, the performance of NR SBD with the wet-etching process is substantially improved, delivering a forward turn-on voltage of 0.65 V, a current density of ∼10 kA/cm2 at 3 V, an ideality factor of 1.03, an ON/OFF current ratio of ∼1010, and no severe current collapse, along with a reverse breakdown voltage of 772 V.