High density plasma is required for plasma processing in future ULSI fabrication. In this study, 2.45 GHz microwave of the TM01 mode in the circular wave guide was introduced through a dielectric disk plate window for generation of excited surface wave plasma. A high dose ion implanted resist ashing is performed using this apparatus. In the temperature rangeof 60 to 150 ℃, ashing rate for neutral hydrogen irradiation is higher than that of oxygen plasma. The results indicate that resist removal by hydrogen atoms is advantageous to enableto oxygen free and low temperature ashing.