Thin films of amorphous hydrogenated silicon tin (a-SiSnx:H) have been prepared by ion beam assisted deposition (IBAD). This technique produces films with a high degree of stability and reproducibility. Ion bombardment at a moderate energy (similar to 100 eV) led to a significant improvement in the structural, electrical and optical properties of a-SiSnx-H films made at a substrate temperature of 210 degrees C. Evidence of the improvement in the material properties has been observed in the increased hydrogen content, decreased defect density, decreased room temperature conductivity, increased photoconductivity, reduced SiH2 and (SiH2) bonding configurations and increased SnH bonding configurations. The material properties of the a-SiSnx:H films created with the ion beam degrade with increased Sn concentration, but at a rate much slower than for samples created without the aid of an ion beam, Infrared studies of the samples created with an ion beam revealed a significant reduction in the preferential attachment of hydrogen to Si rather than to Sn.