Advances in Micro-Transfer Printing of Lithium Niobate Thin-Films for Silicon Photonic Devices.

Silicon and silicon nitride waveguide platforms have established themselves as ideal candidates for high-volume photonic integration, owing to their compatibility with mature semiconductor manufacturing processes. In parallel, lithium niobate has garnered significant attention for its superior electro-optic and nonlinear properties, positioning it as a key enabler for high-speed and advanced photonic functionalities. Nonetheless, the heterogeneous integration of lithium niobate with silicon photonics remains a technical challenge and an active area of investigation. We provide a comparative analysis of integration methods, detail the microtransfer printing process flow and highlight key demonstrators, including modulators, nonlinear devices and emerging applications such as optomechanics and quantum photonics. The scalability of microtransfer printing is discussed in the context of high-volume manufacturing. This review underscores the potential of microtransfer printing to bridge the gap between high-performance lithium niobate devices and industrial-scale photonic integration.