Low Loss and Cost Thin Film for Frequency Adaptive Electronics

Microwave resonators of linear dielectrics for wireless applications have been fabricated in bulk form using conventional ceramic processing in the current commercial market. Machining and fine polishing are frequently required for dimension control and surface finish in addition to the inherent unfeasibility to fabricate miniaturized electronic circuits. It is vital to develop a suitable thin film technique capable of producing commercially viable, high-performance, low-loss, field adaptable oxide films for telecommunications. Thin film devices have been deposited using various CVD techniques, including MOCVD, PECVD, and LPCVD. However, these approaches are limited by the existing precursors of low vapor pressure, high toxicity, and high cost, in addition to the high capital investment in vacuum systems and reaction chambers. Therefore, the aforementioned CVD techniques are not cost effective, as compared to the newly invented combustion CVD at MicroCoating Technologies. Over 90% savings have been demonstrated using CCVD, compared to traditional CVD, with increased deposition flexibility and production-friendliness. The thin films produced in open atmosphere using the CCVD have comparable quality to CVD films. The CCVD also allows substrates to be passed through a deposition zone in a production line for large area coatings. Ba(1-x)Sr(x)TiO(3) and SrTiO(3) are the primary candidates for filter and oscillator applications, due to their high dielectric constants and low loss. Epitaxial YIG is another potential material for microwave filters. Polycrystalline spinel and hexagonal ferrites as well as perovskite ferroelectrics are candidates for tunable phase shifters. Based on past experiences, quality thin films will be grown. The microstructure and electromagnetic properties of the thin films will be characterized. The performance will be optimized and reproducibility will be demonstrated. The above devices are desired for frequency agile filters, oscillators, phase shifters and antennas, impacting on commercial and military applications. These devices can also be easily configured to function as circulators, isolators, DRAM, etc. The CCVD was featured in CNN's Future Watch and Dollars and Sense and in Business Week. American Ceramic Society Bulletin cited CCVD as one of the top five new ceramic coating technologies of the 90's. In April 97, MCT transformed its first completed Phase II into multi-million dollar Phase III funding.