BN/BNSiO2 sputtering yield shape profiles under stationary plasma thruster operating conditions

Abstract

Quartz Crystal Microbalance (QCM) is used to measure the volumetric and total sputtering yield of Boron Nitride (BN) and Boron Nitride Silicon Dioxide (BNSiO2) bombarded by Xenon ions in the energy range of 100 eV to 550 eV. Sputtering yield shape profiles are reported at various angles of incidence 0-85° with surface normal and compared with modified Zhang model. The yield shape profile is found to be symmetric at normal incidence and asymmetric at oblique incidence. Both the materials show a sudden jump in the sputtering yield above 500 eV and at an angle of incidence in the range of 45-65°. Erosion of BN at as low as 74 eV ion energy is predicted using generalized Bohdansky model. BNSiO2 show a marginally higher sputtering yield compare to BN.

Numerical Modeling of Erosion in Hall Effect Thrusters

“…For the sputtering model, the recent experimental measurements of Xe ions impacting on Borosil at room temperature (300 K) by Ranjan et al [13] were selected.…”

“…Figures 8 and 9 report, respectively, the dependence of sputter yield on energy and angle, as measured by Ranjan et al [13] compared to those collected by Garnier et al [32], whose data were widely used to built the sputtering models available in the open literature (cfr. Appendix A).…”

“…Because the study of Ranjan et al [13] lacks data for energies lower than 100 eV (of interest to HETs application) and angles higher than 90°, extrapolations were required.…”

“…The most recent sputtering data regarding the Xe-Borosil couple by Ranjan et al [13] has never been considered.…”

Wall Ion Loss Reduction by Acceleration Zone Shifting in Anode-Layer Hall Thruster

“…𝑌 𝜃 is a normalized quantity relative to the case of normal incidence. Several studies have shown that 𝑌 𝜃 generally increases as the incident angle of the impact ion increases, and 𝑌 𝜃 has a peak when the incident angle is around 45-80 deg [19,20]. In the thruster operation with the magnetic screens, the axial acceleration inside the channel was negligible compared with the radial acceleration due to the potential drop in 𝑉 d toward the guard rings, concerning the ions colliding with the walls.…”