AlN SAW structures for GHz applications

SAW type structures for an operating frequency of about 2.8 GHz and 3.2 GHz have been successfully developed on a thin A1N layer sputtered on high resistivity silicon. Nanolithography was used to manufacture the interdigitated transducer. Fingers and interdigits 300nm and 150nm have been manufactured. A thinner metalization on the IDT will contribute to improve the frequency performances of the devices. We are now developing SAW structures with nanometric IDTs on thin GaN layers. These structures have the advantage in the possibility of monolithic integration with other circuit elements, like HEMT transistors. Future development of WBG semiconductors and nanolithography based techniques will permit the developing of a new generation of SAW devices, operating over 5 GHz, able to be to used in 4G mobile phones and in 5.2 GHz WLAN applications.