Analysis and Design for Inductively Coupled Plasma Power Source with Multi-level Power Mode

The inductively coupled plasma (ICP) source is widely used in the semiconductor manufacturing industry. The main challenge is delivering a high frequency and low harmonic current with multi-level power modulation. The multi-level power mode is required for advanced manufacturing processes and it modulates the output power repeatedly, the energy storage components charge and discharge rapidly, leading to very large transient power losses on switches, especially for the lagging bridge which loses ZVS operation. This paper discussed the matching network design for the ICP source and the steady-state analysis for its phase-shift modulation. Furthermore, the transient power loss mechanism during the multi-level power modulation is elaborated by using multiple harmonic approximation. Finally, the design guidance for ICP source working at multi-level power mode is discussed to achieve high efficiency and high reliability. A 2kW prototyping system is built to validate the proposed analysis and design for the ICP source.