  The thermally-induced structural evolution of silicon- and oxygen-containing
hydrogenated amorphous carbon (a-C:H:Si:O) was investigated by X-ray
photoelectron and absorption spectroscopy, as well as molecular dynamics (MD)
simulations. The spectroscopic results indicate that the introduction of Si and
O in hydrogenated amorphous carbon (a-C:H) increases the activation energy for
the conversion of sp3- to sp2-bonded C. MD simulations indicate that the higher
thermal stability of a-C:H:Si:O compared to a-C:H derives from the lower
fraction of strained C-C sp3 bonds in a-C:H:Si:O.
