In this study, fabricated 320 × 256 infrared focal plane arrays (FPAs) were realised using a GaSb/InAs-based type-II superlattice heterostructure for midwave infrared (MWIR) imaging. We report here the optimized fabrication and characterization of single-pixel infrared detectors and FPAs. MWIR spectral response up to 5 μm of these single-pixel detectors was evident up to 250 K. Responsivity was measured to be 1.62 A/W at 0.8 V and 80 K. Current–voltage characteristics at room temperature (300 K) and at low temperature (18 K) revealed the resistance and dark current variation of the device in the operating bias region. Moreover, good thermal images were obtained at device temperatures up to 150 K for low-temperature targets. Low noise equivalent difference in temperature was measured to be 58 mK at 50 K and 117 mK at 120 K.
Ga-free InAs/InAsSb type-II superlattice (T2SL) photodetector for high operating temperature in the midwave infrared spectral domain