27 February 2012 Effects of polarization fields on avalanche breakdown of AlGaN quantum-well photodiode
Author Affiliations +
Polarization-induced electric fields in AlGaN quantum wells have important effects on avalanche breakdown of AlGaN quantum-well photodiodes. When the polarization-induced fields within the AlGaN well layers have the same direction as applied electric field, they can help enhance impact ionization rate and decrease threshold voltage of avalanche breakdown of AlGaN avalanche photodiodes. However, according to previous research on avalanche breakdown of AlGaN photodiodes, no distinct breakdown threshold was observed from current-voltage curve. Instead, a soft avalanche breakdown was observed across applied voltage ranging from zero to a few volts while electroluminescence spectra show a threshold of about 10 V for avalanche breakdown. In this work, by considering impact ionization of defect levels and carrier screening effect, impact ionization coefficients are calculated as functions of applied voltage and the soft breakdown is well explained. It is also found that strong carrier screening effect will decrease impact ionization rate in a certain range of voltage thus affecting device performance.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Sheng-Kun Zhang, Sheng-Kun Zhang, Wubao Wang, Wubao Wang, Robert R. Alfano, Robert R. Alfano, Amir M. Dabiran, Amir M. Dabiran, Andrew M. Wowchak, Andrew M. Wowchak, Peter P. Chow, Peter P. Chow, } "Effects of polarization fields on avalanche breakdown of AlGaN quantum-well photodiode", Proc. SPIE 8262, Gallium Nitride Materials and Devices VII, 826227 (27 February 2012); doi: 10.1117/12.910189; https://doi.org/10.1117/12.910189


III-nitride avalanche photodiodes
Proceedings of SPIE (February 02 2007)
Photodetectors: UV to IR
Proceedings of SPIE (August 14 2003)
Photodetectors: UV to IR
Proceedings of SPIE (July 01 2003)
Advances in UV sensitive visible blind GaN-based APDs
Proceedings of SPIE (January 24 2011)

Back to Top