Assessment of large format InP/InGaAs quantum well infrared photodetector focal plane array

We report the fabrication and characteristics of large format (640 × 512) InP/In0.53Ga0.47As long wavelength infrared (LWIR) quantum well infrared photodetector (QWIP) focal plane array (FPA). The FPA, which is hybridized to a read-out integrated circuit having a charge capacity of 1.1 × 107 electrons, yielded a mean noise equivalent temperature difference (NETD) of ∼40 mK at a cold finger temperature as high as 77 K. The performance of the FPA, being comparable to that of AlGaAs/GaAs QWIP FPAs, clearly demonstrates the feasibility of the InP/InGaAs material system as an Al-free alternative to AlGaAs/GaAs system for large format LWIR QWIP FPAs.