| Popis: |
The MOVPE deposition of semiconductors requires effective substrate surface preparation, especially where low temperature, photo-assisted growth is involved. Ideally this process should be achieved in situ in the growth reactor immediately prior to deposition. In a previous paper(1) we reported the in situ removal of carbon from Si and GaAs substrate surfaces using 193nm radiation in a 1 Torr 02 ambient. This process generates a thin oxide which can then be removed by annealing at 850°C, although the process does not always go to completion. To protect the cleaned surface and to passivate the silicon substrate prior to deposition of GaAs we have explored the arsenic passivation techniques developed by Bringans et al(2,3) The oxidation resistance of surfaces prepared this way is also sufficient to permit transfer between laboratories for collaborative studies. |
