A 4H-SiC based separate-absorption-multiplication (SAM) avalanche photodiode with a nanoscale multiplication region and a bulk absorption region is proposed and its optoelectronic performance is modeled. The results show that the avalanche breakdown voltage of the device is found to be dependent on the illumination condition. This is attributed to the existence of an illumination-dependent hole potential well in the upper center of the absorption region. Based on the illumination-dependence of avalanche breakdown voltage, a self-quenching and an ultrahigh UV/visible rejection ratio have been realized in this structure.
© 2012 Optical Society of America
Original Manuscript: May 21, 2012
Revised Manuscript: July 19, 2012
Manuscript Accepted: July 19, 2012
Published: August 28, 2012
Rongdun Hong, Yi Zhou, Yannan Xie, Xiaping Chen, Zifeng Zhang, Kang L. Wang, and Zhengyun Wu, "Nanoscale avalanche photodiode with self-quenching and ultrahigh ultraviolet/visible rejection ratio," Opt. Lett. 37, 3651-3653 (2012)