Frequency-Agile Ka-band Filters Based on Functionally Graded BST Thin Films

In this STTR program, Structured Materials Industries, Inc. www.structuredmaterials.com (SMI) will develop compact, efficient, radio frequency filters, that are widely tunable within the Ka-band (26 to 40 GHz). The tunable Ka-band filters will have properties not possible using present technology, including; high speed, low loss, low insertion loss and excellent temperature stability. Our technical approach will utilize tunable dielectric thin films, based on barium strontium titanate (BST). We will utilize functional grading to improve tunability and temperature stability of the films. We will also utilize metallic acceptor doping to reduce dielectric losses. In Phase I, we will optimize and demonstrate test device structures, through a combined theoretical and experimental approach. We will also develop optimized filter designs, to take maximum advantage of the optimized materials. In Phase II, we will develop and demonstrate fully functional and fully packaged tunable Ka-band filter prototypes. Also during Phase II, we will optimize low cost-of-ownership processes for depositing the optimized BST film structures by MOCVD. In Phase III, we will implement and commercialize the results for both military and commercial markets.