Non-Linear Device Applications of Nano-Patterned Barium Strontium Titanate Thin Films

University Of South Florida, Tampa FL

Investigators

Abstract

Objective - The objective of this research is to investigate the non-linear properties of nano-scale active regions of barium strontium titanate (BST) thin films, their dependence upon deposition and patterning processes, and their manifestation in macro-scale observables including capacitance-voltage behavior. Important goals for this project include the development of non-linear computer-aided-design models and design techniques for BST circuits based on non-linear transmission line topologies. The approach is to use planar capacitor (varactor) structures, layered on a BST film, as the building block for more complex devices. The structures will be patterned using focused ion beam (FIB) milling to create nano-scale gaps. Intellectual Merit - The varactors that will be developed have feature sizes on the same order of magnitude as the film's surface roughness - at this scale, the homogeneity of the film and resultant capacitance-voltage properties, switching speed and dielectric relaxation are not well understood. The exploitation of BST for microwave signal generation will require a thorough understanding of the non-linear properties and advancements in modeling methodologies. Broader Impact - The devices that will be developed can have a great impact on society at large, as the functionality is integral to specialized systems such as military radar and many commercial telecommunications systems. Furthermore, the fundamental knowledge gained on non-linear behavior of BST will be useful to engineers and physicists working in related fields such as high-density memory. The PIs have a track-record of involving under-represented minorities in their research activities and will recruit female and minority students to perform this work.