Rotational and vibrational excitation of sputtered dimers

Optical spectra of molecular species sputtered from nitrogen, and carbon-oxygen implanted silicon are analysed and compared with the predictions of the accompanying theoretical paper. The dominant emission in both systems corresponds to the extensive rovibrational excitation predicted for a sputtering source. The molecules N2, CO, and/or CO+ appear to be the primary electronically excited species. The N2 excitation mechanism in the nitrogen-silicon system is suggested to be similar to that producing the Lewis-Rayleigh afterglow, namely, the associative reaction N(4S0)+N(4S0)reversibleN25Σsub(g)+ followed by the stabilization mechanism N25Σsub(g)++MreversibleN2B3PIsub(g)+M, where M represents the surface. Additional weak SiNB-X, N2C3PIsub(u) and N2+B2Σsub(u)+ excitation is analysed, and its origin discussed. (orig.)