The thermal etching of Si(100) single crystals by F2 has been studied by electron impact (EI) and resonance enhanced multiphoton ionization (REMPI) mass spectroscopy. Laser ionization of the gas phase products observed under single collision gas-surface conditions indicates that SiF2 radicals are formed with an apparent activation energy of 9.9 ± 1.65 kcal/mol. Similarly, EI measurements indicate that SiF4 is desorbed from the surface with an apparent activation energy of 4.0 ± 1.0 kcal/mol. A comparison of the temperature dependence of the ion currents generated by EI for SiFx +, (x = (1-4)) with MPI of SiF2 indicate that the SiFx + signals are derived primarily from SiF2 and SiF4 (possibly vibrationally excited). Both n-type and p-type doping apparently have no significant effect in the measured rates and activation energies for SiF2 and SiF4 production.
|Number of pages||14|
|Journal||High temperature science|
|Issue number||pt 2|
|State||Published - 1 Dec 1988|
|Event||Proceedings of the Sixth International Conference on High Temperatures - Chemistry of Inorganic Materials - Gaithersburg, MD, USA|
Duration: 3 Apr 1989 → 7 Apr 1989