Optical Properties of Europium-Silicate Thin Films Fabricated on Different SiOx Intermediate Layer

We report the effect of SiOx intermediate layers on the photoluminescence properties of europium-silicate thin films. Layer structures of Eu2O3/SiOx/Si (100) were deposited by using an rf-sputtering method and were annealed at 1100 degrees C by rapid thermal annealing (RTA). Two methods were used for the deposition of the SiOx layer: sputtering using a SiO2 target (Ar gas at a rate of 50 sccm) and reactive sputtering using a Si target (Ar gas at a rate of 45 sccm with 02 gas at a rate of 5 sccm). The photoluminescence peak at 430 nm was observed in the sample with a SiOx interlayer sputtered from a SiO2 target. In comparison, a PL peak at 570 nm was observed in the sample where SiOx layer had been deposited by reactive sputtering from a Si target.