Conduction Mechanisms and Low-Frequency Electrical Noise Studies in pin InGaAs/InAlAs Strained MQW Photodiodes

The current–voltage (I–V) characteristics as a function of temperature of different strained multiple-quantum-well pin InGaAs/InAlAs photodiodes were investigated in the dark from 15 K to 300 K. Analysis of the slope variation of the I–V curves as a function of temperature, under forward bias, indicate a conduction mechanism by tunneling effect assisted by recombination centers. For temperatures below around 100 K, as the voltage increases, a negative resistance appears, followed by oscillations suggesting a sequential resonant tunneling between electronic states of the quantum wells. Low frequency electrical noise measurements performed at 300 K between 1 and Hz confirm the existence of recombination centers.