Over the past few years we have been developing a scientific basis for amorphous silicon-based integrated photonics technology. Waveguides using hydrogen-implanted, optically-smooth, hot-wire-deposited films have been prepared and demonstrated, and structures were characterized by Raman spectroscopy of the implanted and the non-implanted regions of the waveguide samples. The analysis is consistent with greater disorder in the film structure induced through implantation. More recently, materials prepared by femtosecond laser ablation of silicon powder have been characterized by Raman spectroscopy indicating a structure having both amorphous and crystalline components. As amorphous silicon photonics continues to evolve, the patterning of materials of differing crystallinity may become an issue of interest.