InSb红外焦平面探测器的区域性过热盲元问题研究

Study of Regional Overheating Dead Pixels in InSb IRFPA Detectors

研究了InSb红外焦平面探测器的区域性过热盲元问题。通过故障分析以及有针对性的排查对比试验,排除了封装、胶水填充和划片等因素,并将故障定位在钝化工艺前。通过对钝化前的InSb材料片表面进行X射线光电子能谱测试,发现它含有Al和As等杂质元素,存在钝化前材料表面杂质含量较多的隐患。杂质元素在PN结的耗尽区形成杂质能级,加载电压后容易导致PN结漏电流较高,使I-V特性退化,从而形成过热盲元。通过缩短器具洗液的更换周期并且分隔使用多个生产线的器具,可以减少材料表面的杂质附着,使区域性过热盲元问题得到有效解决。

Regional overheating dead pixels problems of InSb infrared focal plane detectors was studied.Through fault analysis and targeted investigation and comparison tests,factors such as packaging,glue filling and dicing are eliminated,and the fault is located before the passivation process.Through the X-ray photoelectron spectroscopy test on the surface of InSb materials before passivation,it is found that it contains impurity elements such as Al and As,and the surface of the material contains more impurities before passivation.Impurity elements form impurity levels in the depletion region of the PN junction.Impurity elements form impurity levels in the depletion region of the PN junction.After voltage is applied,it is easy to cause high leakage current of the PN junction,degrade the I-V characteristics,and form overheating dead pixels.By reducing the washing liquid replacement period of the cleaning appliance and separating the appliances of multiple production lines,the content of impurities on the surface of the material is reduced,and the problem of regional overheating dead pixels is effectively solved.