Efficient Optimization Design of Microwave Plasma Slot Antenna Structures Based on Rectangular Waveguide

Microwave plasma sources are used in nitride thin film deposition owing to their superior thin film characteristics and low processing temperatures. Slot antenna optimization was examined using finite element electromagnetic simulations to enhance power transfer efficiency and spatial uniformity related to individual slot propagation in microwave plasma sources. The propagation efficiency was measured based on the structure and position of the slot antenna by configuring the slot antennas in various orientations, including transverse, longitudinal, waveguide-rotated longitudinal, and hybrid slots. For the four types of slot positions, the lengths of the major and minor axes were varied from 5 to 60 mm and 2 to 10 mm, respectively. The increase in electromagnetic wave transmission through the slots and the power transfer uniformity according to individual slots depended on the major axis length, showing optimization at 50 55 mm.