The Need

Photonic integration is driven by demand for smaller size, lower cost, lower power consumption, easier assembly, higher reliability, and greater data density in modern photonic devices and systems. Among the many platforms, silicon photonics is particularly promising for photonic integration due to the leveraging of existing electronics integrated circuit facilities for large-scale manufacturing. However, due to the limited active properties of silicon, monolithic integration in silicon is challenging, which creates a need for hybrid integration. Hybrid silicon and lithium niobate is one excample of a system that has been developed recently, but current methods of fabrication suffer from many drawbacks, such as exfoliation of lithium niobate plateletes from the bulk wafer, slow etching rates, plateletes of uncontrolled size, shape, and unknown orientation of the crystal axes. A new method of hybrid silicon system fabrication needs to be developed in order for these systems to see widespread use.

The Technology

Researchers at The Ohio State University, led by Ronald Reano, have developed a novel technique to obtain patterned thin films of lithium niobate from crystalline substrates. Instead of randomly sized platelets from conventional techniques, the method produces thin films with controlled shape, and crystal orientation. The patterned thin films enable hybrid integrated photonics that exploit the electro-optical and non-linear optical properties of lithium niobate to realize a host of chip-scale devices. In addition to lithium niobate, the technique can be applied to other materials for wireless and optical applications.

Commercial Applications

• Modulators, switches, filters, and sensors for communications, computing, and sensing industries
• Flexible photonics
• Thin-film wave plates
• Hybrid integration with planar light wave circuits

Benefits/Advantages

• Precise and reproducible fabrication of patterned thin films of ion-sliced lithium niobate for hybrid photonic integration on silicon with controlled size, shape, and crystal orientation
• Enhanced functionality and performance of thin film devices due to optimal alignment and orientation of crystal domains
• Reduced cost and waste of material due to efficient use of crystal substrates
• Hybrid integration of lithium niobate and silicon wave guides enables compact hybrid integrated optics leveraged by the second order nature of lithium niobate
• High optical confinement and integrated electrode design enables large electric fields in the lithium niobate and large phase tuning efficiency
• Increased compatibility and integration of thin films with different materials and platforms