RFMEMS resonators and filters built in thick oxide insulator (TOI) A1N platform

Abstract

We report a variety of CMOS-compatible radio frequency micro electromechanical system (RFMEMS) devices that are built within a high performance platform suitable for RF applications. Resonators and Filters are test vehicles of the platform, which features a thick oxide insulator (TOI) on high resistivity silicon substrate to provide electrical isolation to substrate of radio frequency signals. The first vehicle prototype consists of a bulk acoustic wave (BAW) filter with central frequency of 2.44GHz, insertion losses less than 1.5 dB, out-of-band rejection better than 30 dB, and bandwidth higher than 60 MHz. These figures make the filter suitable for wireless LAN and mobile applications in the 2.44 GHz band. A second test vehicle consists of Lamb-wave resonator banks with a variety of frequencies and that are fabricated in the same chip with quality factors Q> 1,000, large motional impedance range, and low insertion losses. Additional RF test structures help to assess the platform's suitability for RF above 1 GHz.