Predicted Performance Of Indium Antimonide Focal Plane Arrays

Maturity, proven producibility, and superior performance make indium antimonide the preferred choice for mid-wavelength (2 to 5.4 µm) infrared systems. Only at temperatures in excess of 130 K do other detector materials afford advantages over InSb. To realize the high performance inherent to the InSb detectors in large array formats, readouts need to be designed that provide low noise, buffer the InSb to off-focal-plane electronics, and provide the speed dictated by the specific application. For the highest performance the readout needs to be more than a simple matrix of switches. Reset-integrator and buffered-common-gate inputs are discussed and compared to an innovative chopper-stabilization design that uses a carrier modulation technique to upconvert detector signals to higher frequencies where MOSFET 1/f noise is low. Projections of focal plane performance are made for various qualities of InSb detectors interfaced to chopper-stabilized readouts specifically designed for the detector impedances achievable at elevated temperatures (> 100 K).