Enhanced performance QWIP FPAs

We report the pixel and large format FPA level characteristics of strained InP/In0.48Ga0.52As QWIPs to demonstrate the advantages of this material system for LWIR thermal imaging. The grating coupled FPA pixels with responsivity peak and cut-off wavelengths of 8.5 and 9 μm exhibited a peak quantum efficiency as large as 20% which has allowed desirable FPA operation at a temperature as high as 78 K. InP/InGaAs QWIPs, when compared with those constructed with the AlGaAs/GaAs material system, offer the advantage of bias-adjustable gain (in a wide range) as well as higher quantum efficiency resulting in conversion efficiencies significantly higher than those provided by GaAs based QWIPs. These advantages show potential to overcome the limitations of the standard QWIP under high frame rate and/or low background conditions.