Optical Sensing with Sculptured Thin Films

Physical-vapor-deposition techniques are used to assemble 1-to-3-nm clusters into thin films; hence, the nanoscale and microscale morphologies of thin films can be nanoengineered. Sculptured thin films (STFs) are a class of thin films with locally columnar morphology, being assemblies of parallel, shaped nanowires. As morphology and performance are the two faces of the same coin, multifunctional performance expected of metamaterials can be realized by nanoengineering a composite cellular morphology. Their optical and biological functionalities indicate that STFs exemplify nanoengineered metamaterials. Among the more interesting applications of STFs in development is the one for optical sensing of analytes.