A Low Cost, Lightweight Reusable Sensor for Atomic Oxygen Detection

Abstract

Atomic oxygen (AO) erodes many materials used on low Earth orbit (LEO) spacecraft and so it has become necessary to find ways of measuring the AO flux encountered by such vehicles. Many techniques have been used for the measurement of the atomic oxygen environment in LEO; however, their mass and power budgets often preclude their use on microsatellite missions. Those techniques that are suitable for such missions frequently suffer from other limitations such as poor accuracy and the reliance on a coating or a film that, once totally eroded, prevents further measurements of AO fluxes. Thus, there exists no detector entirely suitable for accurate determination of atomic oxygen fluxes on microsatellite missions.Semiconducting detectors offer a promising solution to this problem. Laboratory investigations have shown that an n-type semiconductor experiences an increase in resistance when exposed to a flux of AO. The change in resistance is not permanent; heating the semiconductor to modest temperatures can nearly restore the original resistance. The ability to regenerate the sensor allows further measurements to be performed. Preliminary experimental results of such a device are presented and the development of a lightweight, low cost and low power microsatellite experiment based on these sensors is described.KeywordsAtomic OxygenZinc OxideWitness SampleZinc Oxide FilmSemiconductor SensorThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.