Amorphous silicon-boron-carbon-nitrogen alloys were deposited by reactive magnetron sputtering, and their bonding statistics and electronic structure were investigated using a combined approach of experiment and molecular dynamics simulations. The authors show a difference between Si-based and C-based Si-B-C-N networks, and investigate coordination numbers and behavior of individual atom types. Furthermore, the authors calculate electronic structure and photoconductivity of the materials. The authors find that both a higher Si/C ratio and an addition of hydrogen increase a band gap of the materials. (c) 2007 American Vacuum Society.