Optical and Electron paramagnetic resonance studies of hydrogenated amorphous carbon (a-C:H) thin films formed by direct ion beam deposition method

摘要

The diamond-like carbon films, deposited by direct ion beam deposition method using mixture of C_6H_(14) and H_2 with and without silicon presence, have been investigated by Raman spectroscopy, X-ray photoelectron spectroscopy, ellipsometry, IR-visible-UV transmission, and electron paramagnetic resonance techniques. The D and G line widths and peak positions, integrated intensity ratio (I_D/I_G) in Raman spectra indicate these films being amorphous, mixture of sp_2 and sp_3 bonds. It has been found that a-C:H films formed while increasing substrate temperature and deposition ion energy tend to be graphite-like. Increasing of hydrogen content in gas mixture made these films more polymer-like with low content of dangling bonds. Traces of silicon increase sp_3/sp_2 ratio. The DLC films on silicon are able to greatly reduce IR reflection.