| Autor: |
Vivet, L., Dubreuil, B., Gibert-Legrand, T., Barthe, M. F., Perrin, C., Vivet, L., Dubreuil, B., Gibert-Legrand, T., Barthe, M. F., Perrin, C. |
| Zdroj: |
Journal de Physique III; January 1997, Vol. 7 Issue: 1 p87-98, 12p |
| Abstrakt: |
We have studied the reactivity of NH3on GaAs (100) surface irradiated by 280 nm laser beam at low fluence (< 50 mJ cm-2per pulse) in an experimental set-up which allows a very sensitive characterization of the surface state using mass spectrometry. Thanks to this analysis technique we could follow desorbed NHx$(x = 2,~3)$species during the laser treatment; this phase achieved, GaN+could be identified as an evidence of N fixation using laser desorption mass spectrometry of the treated surface. This characterization mode demonstrates the fluence and laser shot number dependencies on laser treatment efficiency. At 280 nm the N fixation is maximum for laser fluence of about 25 mJ cm-2(per pulse). Still even in the best nitridation conditions, the process appears to be of little efficiency, since it leads to the formation of less than one monolayer of GaN. These results combined with a numerical model of GaAs laser heating give evidence for the laser-induced nitridation to be thermally assisted. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
