Direct bonding conditions of ferrite garnet layer on ion-exchanged glass waveguides

In order to realize an integrated optical isolator, a new hybrid optical structure has been proposed. This structure is composed of an active magneto-optic garnet layer with a strong refractive index, transferred on a passive ion-exchanged glass waveguide. Given the thermal restraints relating to the stability of the glass waveguides, the process used to achieve this hybrid structure is composed of two main steps: firstly, good quality garnet films were grown by liquid phase epitaxy, then these active films were bonded successfully on glass wafer. According to modelling, the thickness of the garnet layer does not exceed 300 nm for maintaining a good confinement. Good wafer bondings on ion-exchanged glass waveguides are obtained.