<title>Long-term stability and uniformity in 2D infrared focal plane arrays</title>

With the increased use of large format detector arrays in IR imaging systems, designers are seeing the limitations that array response nonuniformities place on overall system design, performance, and cost. In many designs where high sensitivities are required and temporal noise has been reduced with the use of high quantum efficiency detectors, response nonuniformity across the array begins to limit the overall system performance. In addition, changes in the pixel response or offset that occur after nonuniformity corrections show up as new nonuniformities that also limit system performance. Because the array response is not adequately stable over time, system designers must include updatable nonuniformity corrections (recorrections) in the hardware or algorithms in the software to remove nonuniformities. We have measured the stability of InSb 2D focal plane arrays including measurements of the residual spatial nonuniformities over time and with temperature cycling. 2D focal plane arrays with stability that allows a one time correction to be used over several days have been measured. To help understand the source of this stability, the sensitivity of the spatial nonuniformity to small changes in the array temperature, detector leakage current, and detector bias was measured. These results are presented here.