提升红外焦平面探测器杜瓦组件的贮存寿命

Improvement of Longest Vacuum Holding-Time in Dewar Assembly for Infrared Focal Plane Array Detector

摘要: 杜瓦内真空度退化和芯片盲元增加是影响红外焦平面探测器杜瓦组件贮存寿命的两大方面。杜瓦组件的排气策略直接关系到红外红外探测器杜瓦的真空寿命和红外芯片的贮存寿命,是影响红外探测器杜瓦组件可靠性的关键。本文以杜瓦放气率测试技术为依托,结合杜瓦组件在贮存环境下的退化规律和模型预测杜瓦贮存寿命。最后,综合平衡排气温度/时间对杜瓦真空寿命及芯片盲元损耗的影响,提供一种实现红外芯片和杜瓦真空同时失效的技术途径。

Abstract: We addressed the two major problems:the pressure build-up in Dewar assembly and increasing blind pixels of infrared focal plane array (IRFPA) detector. First, the surface outgassing of Dewar assembly, compressing Dewar, IRFPA chip and getter material, was mathematically modeled, theoretically analyzed and experimentally evaluated with the lab-built test platform to predict the longest vacuum-holding time. Next, the influence of the baking temperature and time on the storage life of infrared chip was investigated. The results show that the baking temperature and baking time all have a major impact on the simultaneously failure of both vacuum and infrared chip. And finally, the Dewar assembly for an IRFPA detector was tested for optimization of baking conditions. Baked at 90℃ for 16 d, the longest storage time of the Dewar assembly at 30℃ was estimated to be 14y.