High-Efficiency Wide Load Range ZVS RPS Considering Harmonic Analysis

Remote plasma source (RPS) for inductive plasma (ICP) is preferred in the semiconductor industry due to its simple structure and high efficiency. In this paper, a high-efficiency inverter with LCL resonant topology is proposed which can supply high voltage for the initial ignition process and an almost constant output current for sustaining process. By considering the harmonic component, an accurate time-domain expression of resonant current is presented and contributes to parameters design for wide load range ZVS operation. To verify the feasibility of the design and analysis, simulations and experiments are built up at 400kHz with four cases of varied equivalent impedance. The prototype achieves high efficiency over a wide ZVS region with a maximum output power of 3000W.