STRUCTURAL AND COMPOSITIONAL STUDIES OF A-SI,C-H THIN-FILMS OBTAINED EXCIMER LAMP CHEMICAL-VAPOR-DEPOSITION FROM ACETYLENE AND SILANE

Amorphous silicon-carbon thin films were obtained on silicon and steel substrates, by irradiating a mixture of Ar-diluted silane and acetyle ne by Xe-2 excimer lamp in a reaction chamber. The influence of the d eposition parameters on film properties was analyzed by different tech niques, Film composition was determined by Rutherford backscattering s pectroscopy and elastic recoil detection analysis and the structure of the material was studied by infrared and Raman spectroscopies, x-ray photoelectron and Auger electron spectroscopies. Thickness and refract ive index were evaluated by ellipsometry. Structural studies reveal th at carbon and silicon are present in the films mainly forming homonucl ear and hydrogenated bonds. Compositional analyses indicate high carbo n concentrations and only slight variations for dramatical changes of precursor gas mixture composition. Lamp power tuning affects the growt h rate and film density. Moreover, oxygen is incorporated when the lay ers are exposed to the atmosphere forming silicon oxides. (C) 1998 Ame rican Vacuum Society.