Investigation of traps in strained-well InGaAs/GaAsSb quantum well photodiodes

InP-based strained-well InGaAs/GaAsSb quantum well photodiodes with non-zero net strain can be used to extend detection wavelengths well into the mid-infrared region. However, excess dark current due to defects in the structure can be a performance limiting factor in photodiodes of this type. In this reported work, both low-frequency noise spectroscopy and deep level transient spectroscopy were used to investigate traps in prototypical strained-well photodiode heterostructures. Two distinct traps were identified and their electrical and physical properties and distributions have been evaluated.