TALIF Measurement of Dissociation Degree in Pulsed Planar Microwave Hydrogen Plasma

By means of two-photon-absorption laser induced fluorescence (TALIF) at 205 nm the temporal dependences of the absolute atomic hydrogen density were measured in the pulsed planar microwave plasma source. The microwave discharge was operated at 2.45 GHz, the modulation frequency is 500 Hz with 1:1 duty cycle, its power is 0.6 kW in lower power phase and 3.6 kW in higher power phase. The absolute density of atomic hydrogen was obtained by calibrating with NO2 titration in a flow tube reactor. The dissociation degree was determined under different discharge pressures