Hydrogen release behavior from graphite under pulsed laser irradiation

Mass distribution and time variation of the emitted ions by time-of-flight mass spectrometer and desorbed gases by a quadrupole mass spectrometer from the H+-implanted graphite sample by the pulsed ArF (193 nm) laser irradiation have been studied. The averaged ion mass is smaller for the larger laser fluence. Most of the implanted H in the laser irradiated area was released out after a few 10 shots, when the laser fluence is above the ablation threshold. However, the ablation accompanies large amount of hydrocarbon release. Changing the power of the laser, the reduction of hydrocarbon release is studied.