This research project addresses development of methods for fabrication of nanopattemed photonic elements. These compact photonic crystal films resonate sharply when illuminated with light [1. 2]. The attendant spectral and angular signatures are useful in photonic device design and have \'numerous potential applications. It is of . interest to design and optimize resonant pbotonic crystal elements with prescribed filtering, polarization, and security attributes using existing computer codes. Then applying nanoimprint lithography [31 techniques, we fabricate prototype devices using materials produced by Dyrnax Corporation. The initial prototypes are designed for use in the near IR and telecomm spectral regions. We apply commercial gratings (NeViport Corporation, grating period A = 556 nm and 1111 nm) as master templates. With these masters, we have fanned PDMS (silicone) molds to function as stamps for the soft lithography\' steps. The shape of the polymer grating copy is sinusoidal in this case. The PDMS molds generally pe\'cl off the cw-ed polymers easily such that the replica molding method yields good results. Ongoing efforts include measurement of device response. Among the problems encountered are stamp deformation and associated unwanted perturbations on the desired pattern. Additionally, nonuniform pressure distribution and\' shrinkage during cure may cause undesired grating foons. Finally, it is necessary to control the thickness of any residual layers precisely. To produce resonant periodic elements with arbitrary profiles, the masters will be written using electron-beam Iithogmpby. There are several methods at hand for converting the adhesive replicas into resonant devices. Prefabricating a homogeneous waveguide film of high refractive index and curing the periodic replica on top is B possible pathway. Another approach is deposition of h.igh-refractive-index thin films functioning as a waveguide layer on top of the cured polymer grating to make the strucrure resonate. Both have been attempted with the second .showing more promise at this stage. These results will be presented in the conference.

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