Superlattice Si/SiC APD with improved photo-sensitivity and stability: Application as low noise single photon detector

Abstract

This study reports the superiority of superlattice Si/SiC Avalanche Photodiode (APD) over its flat profile Si and SiCcounterparts. A large signal quantum corrected drift-diffusion (LSQC-DD) model is developed and used for the electro optical characteristic studies of the devices for application in UV detection. The effect of charge bump in the optimized doping profile near the metallurgical junction of the Device Under Test (DUT) is studied and reported for the first time in detailed. These results in the betterment of quantum efficiency compared to its flat profile counterpart (95 % vs.91 %). This study also reports the suitability of 3 × 3 array based APD photo sensors in terms of photo responsivity and quantum efficiency. Significant Noise reduction in case of Si/SiC superlattice devices would open its application possibility as low noise single photon detector. The validity of the indigenously developed simulator is established through experimental verification. Fabrication feasibility of the new class of superlattice APD is presented. To the best of authors' knowledge this is the first report on superlattice Si/SiC APD as single photon UV detector.