UV p-i-n PHOTODIODES MADE ON WIDE BANDGAP SEMICONDUCTORS

Abstract

In this paper, results of investigations on the static and dynamic characteristics, responsivity, internal noises, detectivity and noise equivalent power of the forward biased p-i-n photodiode made on wide band gap semiconductors operating in double injection regime are presented. Numerical simulations were made for 4H-SiC and GaN . It is shown that forward biased p-i-n photodiodes have high values of responsivity (~ 0.03 A/W for 4H-SiC and ~ 0.15 A/W for GaN ), detectivity (~1011 cm Hz 1/2 W-1 for 4H-SiC and ~ 8×1013 cm Hz 1/2 W-1 for GaN ) and low level of internal noises at room temperature. It is shown also that dynamic negative resistance on the current–voltage characteristic can come into existence and that the reactive part of the impedance is the sign-changed function versus frequency.