MEMS tunable bandpass filters on high-k LTCC

This paper describes a novel MEMS tunable bandpass filter, which operates at the Ku band and features an extremely low insertion loss of -1.23-2 dB, a small size of 3.3 mm by 1.7 mm and a wide continuous tuning range of 36%. The tunable filter is based on MEMS-varactors-loaded microstrip resonators and has been directly constructed on a high-k low-temperature-co-fired-ceramics (LTCC) wiring wafer using newly developed MEMS-on-LTCC technology, which allows use of high-k materials as the filter substrate enabling a small size and low insertion loss, and greatly simplifies the fabrication and packaging processes. MEMS-on-LTCC technology combines the advantages of LTCC and MEMS and is promising for future reconfigurable radio front-end modules.