Fabrication and Characterization of RF MEMS Package Based on LTCC Lid Substrate and Gold-Tin Eutectic Bonding

This paper reports on an RF MEMS package based on LTCC technology and gold-tin eutectic bonding, and also evaluates physical and RF characteristics of the proposed structure. The package consists of an LTCC lid substrate and a bottom substrate, and assembled by gold-tin layer (80 wt. % gold 20 wt. % tin) for hermetic sealing and low temperature bonding. The helium leak rate of 17 packages were 1.38 X 10^-8 atm-cc/sec, and the shear strength of the bonded surface showed in the range of 36 - 50 MPa. The RF characteristics were measured up to 10 GHz, and the packaging loss was calculated to be 0.1349 dB at 2 GHz.