Assessment of TEC suitability for a low temperature QCM

Abstract

Quartz crystal microbalances have been used as measuring and monitoring devices for particle deposition on sensitive surfaces such as optical mirrors, thermal radiators, solar arrays, and other equipment used in space exploration. Moreover, microbalances have been applied in space to perform thermo-gravimetric analyses in order to infer about the type of volatile and condensable material. When the object of contamination monitoring is an intrinsically cold surface, e.g. a radiator, an effective cooling is required to achieve the same (or slightly lower) condensing temperature. The cooling problem of the microbalance sensing area has found promising solution from the use of thermoelectric coolers, the only compact and lightweight devices that can be housed in a typical microbalance envelope. Nevertheless, performance of the thermoelectric element at low temperature is a known issue so that restricts most applications above −40°C therefore there is a lack of data about performances below that temperature and characterization in expected environment is generally required. Thus, in this work cooling performance of commercial thermoelectric elements has been assessed at low temperature along with its survival to thermal cycling in off condition, in order to assess its applicability for the space borne microbalance under development.