An Efficient Method for Fabricating Three-Dimensional Photonic Crystal Structures with Engineered Defects using High Index Polymer Materials.

In this proposal we will develop a general method for fabricating 3D polymer based Photonic Crystal structures (PhCs) with engineered defects. The criterions of such a method include the generality of producing various periodic arrangements of 2D, 3D PhCs with or without aperiodic features, compatibility for different polymer materials and their synthetic processes, batch manufacturability for low cost duplication, integratability for tuning elements and extendibility for other fabrication approaches. In this effort, we propose such a fabrication method. Derived from the mature planar lithography, this method accomplishes 3D confined exposure with mask-controlled in-plan patterns and an absorption-controlled vertical exposure depth. Based on specially selected polymer chemistry, new polymer layer can be applied on the top of previously patterned polymer layer. 3D structure can be built up in a layer-by-layer if the above two processes are repeated for multiple times. Depending on the application, the resulted 3D PhCs can act as the final product or intermediate template for the infiltration of desired polymer material. The ability to efficiently fabricate 3D PhC structures with engineered defects will open a new paradigm for tuning the optical as well as the dispersion properties of PhCs using polymers with refractive index as low as 1.4.