Mixture formation of ErxYb2-xSi2O7 and ErxYb2-xO3 on Si for broadening the C-band in an optical amplifier

Thin films composed of polycrystalline ErxYb2-xO3 grains and crystalline ErxYb2-xSi2O7 layers were formed on a Si(111) substrate by RF - sputtering and subsequent thermal annealing in Ar gas ambient up to 1100 °C. The films were characterized by synchrotron radiation grazing incidence X-ray diffraction, cross-sectional transmission microscopy, energy dispersive X-ray spectrometry and micro photoluminescence measurements. In the annealed film of 950 °C it is observed that the I15/2 - I13/2 Er3+photoluminescent transition exhibits simultaneously maximum intensity and peak width at room temperature. This effect satisfies the requirements for broadening the C-band of an optical amplifier on Si.