A 5.8 GHz High-power and High-efficiency Rectifier Circuit with Lateral GaN Schottky Diode for Wireless Power Transfer

In this letter, we propose to implement a microwave lateral GaN Schottky barrier diode (SBD) in a designed 5.8-GHz rectifier circuit for future high-power and high-efficiency wireless power transfer. The low-pressure chemical vapor deposition SiN-passivated lateral GaN SBD demonstrates a low turn- on voltage of 0.38 V, a low on -resistance of 4.5 Ω, a low junction capacitance of 0.32 pF at 0-V bias, and a high breakdown voltage of 164 V, which are essentials for a high-efficiency and high-power rectifying application. By incorporating this lateral GaN SBD in a well-designed 5.8-GHz rectifier circuit, an unprecedented combination of high efficiency and high power is achieved simultaneously. The rectifier circuit demonstrates a high RF/dc conversion efficiency ( η RF/DC) of 71 ± 4.5% with an input power ( P in) of 2.5 W and η RF/DC = 50 ± 4.5% with P in = 6.4 W per single diode, showing the great promise of embracing lateral GaN SBD for future wireless high-power transfer application.