Protective silicon-silicon oxide magnetron sputtered layer for lithium niobate integrated optical circuits

The paper proposes protective silicon-silicon oxide thin film for integrated optical circuits (IOC) based on lithium niobate. Threshold values for silicon layer thickness were experimentally determined. Silicon-silicon oxide layers were deposited on IOC samples with combination of DC unipolar pulsed magnetron sputtering, reactive magnetron sputtering, and plasma enhanced chemical vapor deposition with inductively coupled plasma source (ICP-PECVD). Selection of proper deposition regimes allowed us to obtain thin films demonstrating no attenuation of optical signal.