Photonic integration of lithium niobate micro-ring resonators onto silicon nitride waveguide chips by transfer-printing

The heterogeneous integration of lithium niobate photonic waveguide devices onto a silicon nitride platform via transfer-printing approach has been demonstrated for the first time. A fabrication process was developed to make free-standing membrane compatible with back-end integrated circuits. Micro-ring resonators in format were lithographically defined by using laser direct writing and plasma dry etching. micro-ring then transferred from their host substrate released chip. An all-pass ring resonator transmission spectrum obtained 1.5 {\mu}m 1.6 wavelength range, measured loaded Q-factor larger than 32000.