Investigation of MQW GaInNAs/GaAs p-i-n photodetector

Transient photoconductivity (TPC), detectivity (D), and noise-equivalent power (NEP) in a dilute nitride based GaInNAs/GaAs multiple quantum well photodetector operating at λ >;1.3 μm are investigated at different temperatures from 100 to 300K. In this temperature range the TPC rise time increases from around 2 ns to 4 ns. The decay PC decays exponentially with two time constants; the fast one of about 5 ns which is independent on temperature, is followed by a slower one of 200 ns at T=100 K, and 520 ns at room temperature. The maximum detectivity of the photodetector is 6.6×10⁹cm√(Hz)/W and the minimum NEP is 3.6×10^-11W/√(Hz), indicating a reasonably fast and sensitive low-noise photodetector.