Using a polymeric precursor synthesized from a mixture of cyclopentasilane, white phosphorus, and 1-hexyne, we deposited phosphorus-doped silicon-rich amorphous silicon carbide (a-SiC) films via a solution-based process. Unlike conventional polymeric precursors, this polymer requires neither catalysts nor oxidation for its synthesis and cross-linkage. Therefore, the polymeric precursor is sufficiently pure for effective doping and fabricating semiconducting a-SiC. This study presents the results of a detailed study of the effect of carbon and phosphorus concentrations on the structural, optical, and electrical properties of a-SiC films. The lowest activation energy for these films is 0.39 eV, which leads to an optical gap and a dark conductivity of 2.1 eV and 10(9) cm, respectively. Moreover, these films satisfy the Meyer-Neldel rule for thermally activated conductivity, which indicates that white-phosphorus doping of solution-processed a-SiC produces films with the same characteristics as phosphine-doped vacuum-processed a-SiC.