The breakdown and the current collapse characteristics of high electron mobility transistors(HEMTs)with a low power F-plasma treatment process are investigated. With the increase of F-plasma treatment time, the saturation current decreases, and the threshold voltage shifts to the positive slightly. Through analysis of the Schottky characteristics of the devices with different F-plasma treatment times, it was found that an optimal F-plasma treatment time of 120 s obviously reduced the gate reverse leakage current and improved the breakdown voltage of the devices, but longer F-plasma treatment time than 120 s did not reduce gate reverse leakage current due to plasmadamage.ThecurrentcollapsecharacteristicsoftheHEMTswithF-plasmatreatmentwereevaluatedbydual pulse measurement at different bias voltages and no obvious deterioration of current collapse were found after low power F-plasma treatment. The breakdown and the current collapse characteristics of high electron mobility transistors (HEMTs) with a low power F-plasma treatment process were investigated. With the increase of F-plasma treatment time, the saturation current decreases, and the threshold voltage shifts to the positive slightly. Through analysis of the Schottky characteristics of the devices with different F-plasma treatment times, it was found that an optimal F-plasma treatment time of 120 s obviously reduced the gate reverse leakage current and improved the breakdown voltage of the devices, but longer F-plasma treatment time than 120 s did not reduce gate reverse leakage current due to plasma exposure. current co-flow characteristics of the HEMTs with F-plasmatreatmentwereevaluatedbydual pulse measurement at different bias voltages and no obvious deterioration of current collapse were found after low power F-plasma treatment.