QUARTZ CRYSTAL MICROBALANCE-BASED EXAMINATION OF SPUTTERING PHENOMENA OF RF ION THRUSTERS

In this paper we present the characterization of the sputtering behavior of a RF ion thruster (RIT-10). Sputtered particles are directly detected with a quartz crystal microbalance sensor installed on two pivoting arms which allow angular positioning for a scan across a hemisphere over a target’s surface. Silicon wafer substrates, which can later be analyzed with Rutherford Backscattering Spectrometry, serve as a passive detection installation for deposited sputter material. Additionally, computational models were applied to estimate the xenon ion beam expansion and its theoretical sputtering behavior. Molybdenum and silver are chosen as target materials for primal sputtering measurements, as they are found in thruster and satellite fabrication respectively and hence, are prone to ion impingement on spacecraft equipped with electric thrusters