MOCVD of High Performance Complex Oxide Films for Switchable Film Bulk Acoustic Resonators

In this STTR program, Structured Materials Industries, Inc. (SMI) and partners are developing high efficiency, switchable RF filters. The technical approach is based on thin films of paraelectric BaxSr1-xTiO3 and SrTiO3, which can show piezoelectric behavior under an applied DC bias. When integrated into resonator structures, these materials can act as both an RF filter and an RF switch. Combining these functions will greatly simply manufacture of RF circuits and reduce RF losses, resulting in communication systems with greater efficiency, smaller footprint and reduced cost. The critical enabler for our approach is SMI's metal organic chemical vapor deposition (MOCVD) technology, which can produce complex oxide films of exceptional quality for efficient RF filter operation. In addition, MOCVD provides a direct and quantitative means for compositional grading and compositional doping, which can further enhance device properties such as temperature stability and reduce dielectric loss. MOCVD is scalable to large wafer sizes and high volume production, for ultimate production of the switchable RF filters in high volume and at low cost. MOCVD is also compatible with standard semiconductor fabrication techniques, which will enable a greater degree of integration for the RF filters, for greater functionality and additional cost reduction.