Electrical and optical performances with extracted minority carrier lifetimes of InAs/GaSb SL photodetector operating in the mid wavelength infrared range
Optical and electrical performance of InAs/GaSb based T2SL detector are analysed.
The T2SL structure is designed to operate with high quantum efficiency in the MWIR.
Band structure of T2SL are analysed by SEPM calculations.
Minority carrier lifetimes are highly important for understanding of carrier transport and improving the device performance.
Shockley Model is used to extract the minority carrier lifetimes from temperature dependence of J-V measurements.
We report a study on the temperature dependence of electrical and optical performance of InAs/GaSb based type-II superlattice (T2SL) pin photodetectors in the mid wavelength infrared range (MWIR). The SL structure exhibits an optical response of 50% cut-off wavelength at 4.9 μm at 79 K. Deduced from current density–voltage (J–V) measurements, dark current density under 0.1 V reverse bias is measured as 7.6 × 10−6 A/cm2 with a corresponding differential–resistance–area product (R0A) of 3.3 × 104 Ωcm2 at 100 K. Minority carrier lifetimes of the T2SL detectors are analysed by Shockley's Model where experimental data for dark current densities are fitted by diffusion and generation-recombination (GR) components at different temperatures.