The Applied Power Electronics Conference (APEC) 2026
This paper proposes a practical circuit topology and con-trol method for a high-frequency power supply used in plasma etching systems. As semiconductor device dimen-sions continue to shrink, highly precise etching technolo-gy is required, and control of the ion energy distribution has become increasingly important. In particular, the temporal slope of the power-supply voltage waveform significantly affects the ion energy density. Therefore, this study focuses on improving the ion energy density by employing a negative-polarity triangular waveform as the power-supply voltage. Conventional studies use power amplifiers, but these may suffer from low efficiency. Therefore, we propose a switching-power-converter-based topology and control scheme that allows arbitrary adjustment of both the amplitude and frequency of the output voltage waveform. While a transformer-based configuration was introduced in a previous digest, this paper presents a new, simpler, and more efficient topolo-gy that does not require a transformer. Using a prototype circuit, we demonstrate that a highly linear triangular-wave output can be achieved at approximately 400 kHz.
