Methods for forming non-oxygen containing silicon-based films, that contain >50 atomic % of silicon, are provided herein. In one aspect, the silicon-based films have a composition SixCyNz wherein x is about 51 to 100, y is 0 to 49, and z is 0 to 50 atomic weight (wt.) percent (%) as measured by XPS. In one embodiment, the non-oxygen silicon-based films were deposited using at least one organosilicon precursor having at least two SiH3 groups with at least one C2-3 linkage between silicon atoms such as 1,4-disilabutane.