Simulation and experimental analysis of a miniature ion thruster fabricated in low temperature co-fired ceramic

Summary form only given. Scaling down electric propulsion systems is of interest for the future development of propulsion systems for micro- and nano-satellites. Because of the low mass of nano-satellites, only a small amount of thrust, on the order of several hundred μN, is needed for tasks such as attitude control. An Inductively Coupled Plasma source (ICP), fabricated in Low Temperature Co-fired Ceramic (LTCC), has been developed. The ICP is now being integrated into a miniature ion thruster, with a diameter of approximately 2cm; the thruster body is also made of LTCC. The design of the antenna for the ICP has been optimized to generate the maximum electric field at a peak frequency in the range of 450MHz-1GHz. The antenna design was simulated using COMSOL Multiphysics modeling software, and the antenna field pattern has been verified experimentally. Plasma generated by the ICP will be characterized by a Langmuir probe at several frequencies in order to determine the optimum frequency that will create the densest plasma with minimal rf power. Measurements with the Langmuir probe will be performed in three configurations: the ICP by itself, the ICP with a 2cm diameter LTCC cylindrical tube surrounding the ICP antenna, and finally the ICP with the LTCC tube and two rings of magnets alternating in polarity to create a magnetic cusp. A two-gridded electrical system will be employed in order to extract ions from the thruster and create thrust. The screen grid, the closest grid to the plasma, will be biased at 1000V while the second grid, the accelerator grid, will be biased to -200V. Ions will accelerate through this electric potential. Beam divergence and thrust will be measured with a collector plate at varying distances from the thruster. Three collector plates will be used: a radial pad layout, an azimuthal pad layout, and a single pad layout in order to measure the radial pattern, azimuthal pattern, and total thrust, respectively. The simulated and exper- mental results will be presented.