In this paper, we present a three-dimensional(3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system(RF MEMS) resonator, in which low-loss silicon vias is used to tran...In this paper, we present a three-dimensional(3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system(RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals.Au–Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio(SBR) of 24 dB is achieved, as well as the quality factor(Q-factor) of the resonator increases from 8000 to 10400 after packaging.The packaged resonator has a linear frequency–temperature( f –T) characteristic in a temperature range between 0℃ and 100℃. And the package shows favorable long-term stability of the Q-factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.61234007,61404136,and 61504130)the Fund from the Ministry of Science and Technology of China(Grant No.2013YQ16055103)+1 种基金the Key Research&Development Program of Jiangsu Province,China(Grant No.BE2016007-2)the Major Project of Natural Science Research of the Higher Education Institutions of Jiangsu Province,China(Grant No.16KJA510006)
文摘In this paper, we present a three-dimensional(3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system(RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals.Au–Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio(SBR) of 24 dB is achieved, as well as the quality factor(Q-factor) of the resonator increases from 8000 to 10400 after packaging.The packaged resonator has a linear frequency–temperature( f –T) characteristic in a temperature range between 0℃ and 100℃. And the package shows favorable long-term stability of the Q-factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples.