Analysis and design of a 2.45 GHz RF power source for a miniature electron cyclotron resonance ion source

A high-power solid-sate based radio frequency power source is introduced in this paper. Solid-state based amplifiers are much more efficient than microwave tubes and can be used in compact electron cyclotron resonance (ECR) ion sources. A reliable negative bias voltage controller is proposed to drive the power source’s main power amplifier, which can deliver up to 300 W power to the ion chamber. The selected high-power transistor is internally matched on the input side but the output side is matched in this paper to deliver maximum power to the load. The bias circuit was fabricated on an FR4 substrate and measurement results were obtained to verify the functionality of the bias sequencer. Analog simulations were done by LTSPICE and high-frequency simulations are performed with the momentum RF simulator of Advanced Design System (ADS). The output power of the proposed structure is tunable with 0.5 dB resolution and can deliver 300 mW to 300 W power to the ion chamber.