Optimized design of lateral PIN photodiodes regarding responsivity and SNR as a function of operating temperature

Abstract

This paper addresses a simultaneous analysis of the intrinsic length (L1) and the operating temperature, which are, respectively, a preeminent design variable and a fundamental boundary condition for lateral PIN photodiodes. The analysis is focused in the responsivity and signal-to-noise ratio (SNR), in order to investigate the best configuration for a given technology. CMOS PIN photodiodes with different characteristics were designed and fabricated Experimental measurements were performed and the optical devices showed reasonable performance in the visible spectrum. The best responsivity (37%) was achieved for L1 = 11 μm, at room temperature and light wavelength of 650 nm. The best signal-to-noise ratio was found to be 6000 for red and 700 for blue lights, both at T = 200 K.