J. Phys. Colloques
Volume 47, Numéro C8, Décembre 1986EXAFS and Near Edge Structure IV
|Page(s)||C8-357 - C8-361|
J. Phys. Colloques 47 (1986) C8-357-C8-361
AMORPHOUS HYDROGENATED ALLOYS : A COMPARATIVE EXAFS STUDY OF a-Si1-xCx : H, a-Si1- xGex : H, a-SiNx : H AT THE SILICON K-EDGEA. FILIPPONI1, P. FIORINI1, F. EVANGELISTI1, A. BALERNA2 et S. MOBILIO2
1 Dipartimento di Fisica, Università "La Sapienza", I-00185 Roma, Italy
2 INFN Laboratori Nazionali di Frascati, C.P. 13, I-00044 Frascati, Italy
a-Si1-xCx : H, a-Si1-xGex : H, a-SiNx : H alloys have been studied at the Si K-edge. Si-Si and Si-A (A being C, N, Ge) bond lengths have been determined as a function of composition. The Si-C distance was found to vary significantly, while the Si-Ge and Si-N distances remain almost constant. A high frequency signal has been detected in the a-Si1-xCx : H and a-SiNx : H films at large x due to a second shell contribution. The compositions of the first coordination shell are also reported and discussed in terms of different local coordination models.