Absorption Coefficient, Mobility and Carrier Lifetime Calculations of P-I-P Quantum Dot Infrared Photodetectors

Unipolar, hole-based p-i-p Quantum Dot Infrared Photodetectors (QDIPs) are modeled for the estimation of dark current, mobility and optical absorption parameters. Thermionic and field assisted tunneling are used for modelling of QDIP dark current. For carrier lifetime calculation, the Shockley-Read-Hall (SRH) model (trap-assisted recombination) is used. Utilizing the dark current data and carrier lifetime, optical generation rate is calculated. The relation of optical generation rate with the incident optical power is used to find the absorption coefficient and this ultimately used to find the QDIP efficiency. Mobility $(\mu)$ of 61 cm
²
/V-Sec, Life Time $(\tau)$ of 100 ps, Optical Generation Rate $\left(G_{op}\right)$ of $\sim 1 \times 10^{19} \mathrm{~cm}^{-3}$, Absorption Coefficient $(\alpha)$ of $10^{5} \mathrm{~cm}^{-1}$, Efficiency $(\eta)$ of ~60-65 % are estimated.