InSb红外焦平面探测器十字盲元问题的研究

Study of Cross-shaped Dead Pixels in InSb IRFPA Detectors

InSb红外焦平面探测器在中波红外波段占据重要地位,但十字盲元问题严重降低了探测器的性能。通过聚焦离子束定位剥离手段,发现了十字盲元区域的铟凸点失效。进一步检测发现,铟凸点制备参数欠佳。通过改进铟凸点形状和增加高度,加强了焊接面的牢固度。此后发现极少InSb器件存在十字盲元问题。在80℃下对铟凸点改进后的InSb红外器件进行了14天烘烤。经测试,十字盲元数目保持不变,铟凸点的可靠性较好。改进铟凸点制备技术可有效解决十字盲元问题。互连失效是十字盲元问题的主要原因。以此类推,该方法可解决所有InSb红外器件的十字盲元问题。

InSb infrared focal plane array(IRFPA)detectors are playing important roles in the medium wave infrared band.But cross-shaped dead pixels severely reduce the performance of the detectors.It was found that indium bumps were invalid in the cross-shaped dead pixels′regions by focused ion beam technology.Further inspection revealed that the indium bump preparation parameters were not good.Through improving the shape of the indium bumps and increasing the height,the firmness of the welding surface was strengthened,very few InSb detectors had the problem of cross-shaped dead pixels.The optimized InSb infrared detectors were baked at 80℃for 14 days,and the number of cross-shaped dead pixels remained unchanged after testing.The reliability of indium bumps was good.Optimizing indium bump preparation technology can effectively solve the cross-shaped dead pixels problem.Interconnection failure is the main cause of the cross-shaped dead pixels problem.By analogy,this method can solve the cross-shaped dead pixels problem of all InSb infrared detectors.