CHOICE AND PREPARATION OF ELECTRICAL RESISTANCE FILM MATERIALS FOR ATOMIC OXYGEN SENSORS

摘要

Beijing institute of spacecraft environment engineering has been developing a small, low-cost sensor for detecting atomic oxygen environment and its effects. The sensor bases upon an electrical resistance film which is made of some susceptible conductive materials to atomic oxygen. Up to now, suitable atomic oxygen sensing conductive materials include silver, osmium and carbon. Silver has very high atomic oxygen reactivity. But its atomic oxygen reactivity is non-linear. The carbon reactivity with atomic oxygen is medium and linear. But its electrical resistance has a poor stability in the harsh space environment. Osmium electrical resistance is very stable in the space environment. Its atomic oxygen reactivity has good linearity. In this paper, osmium has been chosen as electrical resistance material of AO flux sensor. The sensor film has been prepared with electroplating and photoetching. It has a good stability and linear AO reactivity. Silver has been chosen as electrical resistance material of AO effect sensor. The sensor film has been prepared with PVD. It has advantage of quick “switch” speed. Now, a combined detector with 2 AO flux sensors and 6 AO effect sensors has been developed. The detector has been standardized in ground AO simulator and passed the radiation, thermal shock and vibration tests.