Rapid Prediction of Longest Holding-Time of High-Vacuum in Micro-Dewar: An Experimental Study

A novel technique was developed to rapidly predict the longest holding-time of high vacuum in micro-Dewar of infrared detector.First, the long-term thermal outgassing was mathematically modeled, theoretically analyzed and experimentally evaluated.Next, the influence of the elevated storage temperature (30℃) and getter content on the high vacuum holding time was experimentally investigated.The preliminary results show that the thermal outgassing depended strongly on the storage temperature but weakly on the getter content, and that high temperature aging, for a much shorter period of time, is capable of predicting the longest holding-time of high vacuum at room temperature.Finally, a miniaturized (INO MEMS) vacuum gauge, installed inside the micro-Dewar with built-in getter material, significantly reduced the high-temperature storage time from 226 days to~23 days.