Presentation Information
[18p-M_103-9]Residence Time Dependence of Optical Emission Intensity of Atomic Oxygen
in Microwave-Excited Oxygen-Mixed Plasma
〇(M2)Thiha Kyawswar1, Hiroki Taniguchi1, Hnin Thazin Hlaing1, Yamato Hiraoka1, Yusuke Nakano1, Yasunori Tanaka1, Tatsuo Ishijima1 (1.Kanazawa University)
Keywords:
microwave excited plasma,radiation intensity,optical emission spectroscopy
Water plasma ashing is an environmentally friendly alternative for photoresist removal in semiconductor manufacturing. The addition of atomic oxygen to water vapor plasma enhances removal efficiency due to the high reactivity of oxygen radicals. In this study the influence of reactive species on photoresist removal was investigated by analyzing the relationship among gas residence time atomic oxygen emission intensity gas flow rate and total pressure in a microwave excited plasma. The plasma was generated using a 2.45 GHz microwave power source and oxygen gas was supplied under controlled pressures and flow rates. Optical emission spectroscopy was used to evaluate atomic oxygen generation. At higher pressures atomic oxygen emission decreased due to increased electron neutral collisions which reduce excitation efficiency. At lower pressures the emission intensity increased with longer residence time because enhanced energy absorption promoted ionization and dissociation. At short residence times insufficient electron molecule interaction led to reduced atomic oxygen generation. These results clarify the role of residence time and pressure in controlling reactive species generation in water plasma ashing processes.