Erbium-doped hydrogenated amorphous silicon (a-Si:H) thin films were deposited by electron cyclotron resonance plasma enhanced chemical vapor deposition of SiH4 with concurrent sputtering of erbium. The oxygen and carbon contamination levels in all films were 1 X 10(19) and 3 X 10(19) cm(-3), respectively, and the erbium concentrations could be controlled from 0.13 to 1.1 at. % by adjusting the erbium bias voltage. The half width Gamma/2 of the Raman transverse-optic peak of the deposited films ranged from 32+/-1 to 36+/-1 cm(-1), increasing with the increasing Er concentration. Strong 1.54 mu m Er3+ luminescence with little temperature quenching was observed from all samples. The most intense Er3+ luminescence was observed from the as-deposited film with a deposition temperature of 380 degrees C and an erbium concentration of 0.13 at. %, showing that using the present method, erbium-doped a-Si:H films with good erbium optical activity and low structural disorder can be deposited directly while avoiding excessive contamination.