Circulator Technology for Full Integration at the Monolithic Microwave Integrated Circuit (MMIC) Level

This Small Business Innovation Research Phase I program will demonstrate a novel chip-scale magneto-acoustic spin wave (MASW) circulator for use in S-band applications. The MASW concept is based on the velocity non-reciprocity of surface acoustic waves in Aluminum doped Nickel-Zinc ferrite. The program will first simulate and demonstrate the necessary concepts in a simpler, but no less critical device: a microwave isolator. Upon successful demonstration of the isolator, the circulator will be built and tested. The program will also demonstrate the ability to integrate the MASW with RFICs. The integration process will be demonstrated by solder bumping and flip-chipping the MASW onto a test chip. This will allow for measuring the performance of the MASW when integrated, taking into account the effects of the ball soldered connections. The combination of the demonstrated devices and their flipchip integration will result in integration with a GaN-based RFIC design to provide a low-cost, superior front end component in the Phase II program.