Zhang, J.; Wu, R.; Wang, M.; Liang, Y.; Zhou, J.; Wu, M.; Fang, Z.; Chu, W.; Cheng, Y. An Ultra-High-Q Lithium Niobate Microresonator Integrated with a Silicon Nitride Waveguide in the Vertical Configuration for Evanescent Light Coupling. Micromachines2021, 12, 235.
Zhang, J.; Wu, R.; Wang, M.; Liang, Y.; Zhou, J.; Wu, M.; Fang, Z.; Chu, W.; Cheng, Y. An Ultra-High-Q Lithium Niobate Microresonator Integrated with a Silicon Nitride Waveguide in the Vertical Configuration for Evanescent Light Coupling. Micromachines 2021, 12, 235.
Zhang, J.; Wu, R.; Wang, M.; Liang, Y.; Zhou, J.; Wu, M.; Fang, Z.; Chu, W.; Cheng, Y. An Ultra-High-Q Lithium Niobate Microresonator Integrated with a Silicon Nitride Waveguide in the Vertical Configuration for Evanescent Light Coupling. Micromachines2021, 12, 235.
Zhang, J.; Wu, R.; Wang, M.; Liang, Y.; Zhou, J.; Wu, M.; Fang, Z.; Chu, W.; Cheng, Y. An Ultra-High-Q Lithium Niobate Microresonator Integrated with a Silicon Nitride Waveguide in the Vertical Configuration for Evanescent Light Coupling. Micromachines 2021, 12, 235.
Abstract
We demonstrate hybrid integration of a lithium niobate microring resonator with a silicon nitride waveguide in the vertical configuration to achieve efficient light coupling. The microring resonator is fabricated on a lithium niobate on insulator (LNOI) substrate using photolithography assisted chemo-mechanical etching (PLACE). A fused silica cladding layer is deposited on the LNOI ring resonator. The silicon nitride waveguide is further produced on the fused silica cladding layer by first fabricating a trench in the fused silica using focused ion beam (FIB) etching for facilitating the evanescent coupling, followed by formation of the silicon nitride waveguide on the bottom of the trench. The FIB etching ensures the required high positioning accuracy between the waveguide and the ring resonator. We achieve Q-factors as high as 1.4*10^7 with the vertically integrated device.
Copyright:
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