P-doped nanocrystalline hydrogenated silicon oxide (nc-SiOx:H) was developed as a p-layer to increase the performance of thin-film silicon solar cells. The nature of the heterogeneous nanostructure of nc-SiOx:H layers was studied in more detail revealing the importance of high quality amorphous silicon and amorphous silicon oxide tissue for achieving good optical and electrical layer properties. TEM imaging revealed that the layer consists of vertical silicon filaments consisting of randomly oriented crystalline grains and amorphous silicon tissue. Raman Spectroscopy was used to study the properties of the crystalline silicon phase, FTIR spectroscopy was used to study the amorphous silicon tissue in the filaments and the silicon-oxide tissue surrounding them, and XPS was used to determine the elemental composition of the nc-SiOx:H. The correlations between the material properties and the different oxygen and silicon related stretching modes from fitted FTIR scans are discussed. FTIR and Raman spectroscopy are shown to be useful tools for engineering device grade nc-SiOx:H. Amorphous silicon single junction cells, with the integrated nc-SiOx:H p-layer, showed an initial efficiency of 11.4%.