Deposition and 1.54 μm Er3+ luminescent properties of erbium-doped hydrogenated amorphous silicon thin films by electron cyclotron resonance plasma enhanced chemical vapor deposition of SiH4 with concurrent sputtering of erbium

Abstract

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 1×1019 and 3×1019 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 Γ/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 μm 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 °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.