The effect of erbium and oxygen on the photoluminescence intensity of erbium and the composition of a-SiOx:(H, Er, O) films deposited by DC magnetron sputtering

The effect of the oxygen content ( $$C_{O_2 } $$ ) in the gas mixture (20% of SiH4 + 80% of Ar) + O2 and the surface area of an erbium target (S Er) on the composition and Er3+ photoluminescence of amorphous a-SiOx:(H, Er, O) films prepared by dc magnetron sputtering has been investigated. Analysis of the experimental data shows that [Er-O] and [Er-O-Si-O] clusters are formed in the gas plasma due to the competing processes of oxidation and sputtering of Si and Er targets and to the interaction of [Si-O] and [Er-O] clusters with each other and with the oxygen in the gas phase. The discontinuities in the dependences of the contents of erbium-bound oxygen and erbium in a film, and N O Er-O and N Er = f( $$C_{O_2 } $$ , S Er), at $$C_{O_2 } $$ ≈ (5–6.5) mol % supports the hypothesis on the existence of different erbium clusters. The necessary conditions for preparing a-SiOx:(H, Er, O) films with the highest photoluminescence intensity of erbium ions at a wavelength of 1.54 μm are determined.