A Low-Ripple 100 kV High-Voltage Generator for Ion Implantation Applications

Ion implantation is one of the key processes in semiconductor device and integrated circuit manufacturing. It injects charged ions into the wafer surface layer via an accelerating electric field, enabling precise modulation of the material’s electrical properties. As the “power heart” of an ion implantation system, the high-voltage power supply directly determines the energy consistency, spatial distribution uniformity, and process repeatability of the ion beam. As technology nodes continue to shrink to 3 nm and beyond, the ripple coefficient of the high-voltage power supply has become a critical concern. Even millivolt-level ripple can cause ion energy dispersion, leading to implantation depth deviations and non-uniform doping concentrations, thereby degrading chip yield and device reliability. To address this challenge, this paper proposes a high-frequency high-voltage generator based on an IPOS (input-parallel output-series) structure. It uses SiC MOSFET devices and adopts a PWM phase-shift control strategy. Simulation results predict an 86% reduction in peak-to-peak output ripple under interleaved phase-shift control, while experimental results confirm balanced module voltages, 60° interleaved resonant currents, and zero-voltage-switching (ZVS) operation at 100 kV/10 mA output. The switching frequency is tripled compared with conventional IGBT-based designs, reaching 222 kHz. These findings confirm the generator’s effectiveness in meeting the stringent low ripple requirements of advanced ion implantation processes.