Vertical GaNonGaN devices with high power rating and high frequency has been developed rapidly thanks to the emergence of highquality freestanding GaN substrate. This work discusses the fabrication, mechanisms and characterization of the vertical GaN power rectifiers. The vertical GaN Schottky barrier diode (SBD) can exhibit low turnON voltage of 0.55 V(at 0.1 A/cm2) and high breakdown voltage of ~800 V, thanks to the highquality Schottky interface as well as highefficient fluorine ion implantation termination. With the ultrathin AlGaN tunneling enhancement layer, further enhanced turnON voltage (0.43 V) and breakdown voltage (~1 020 V) can be realized. In addition, the vertical GaN power rectifier can exhibit nearzero reverse recovery performance as well as currentcollapsefree performance by using highspeed boardlevel test.