摘要：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 ***–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 *** 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.

摘要：A fully integrated cross-coupled LC tank voltage-controlled oscillator（LC-VCO） using transformer feedback is proposed to achieve a low phase noise and ultra-low-power design even at a supply below the threshold voltage. The ultra-low-power VCO is implemented in the mixed-signal and RF 1P6M 0.18-μm CMOS technology of SMIC. The measured phase noise is-125.3 dBc/Hz at an offset frequency of 1 MHz from a carrier of 2.433 GHz,while the VCO core circuit draws only 640μW from a 0.4-V *** designed VCO can cover a frequency range from 2.28 to 2.48 *** tuning range of the circuit is 200 MHz（8.7%） and the FOM is-195.7 dB,which is suitable for an IEEE 802.11b receiver.

摘要：Hexagonal boron nitride(h-BN)is found to have widespread application,owing to its outstanding properties,including gate dielectrics,passivation layers,and tunneling *** current studies on the funda⁃mental physical properties of these ultrathin h-BN films and the electron tunneling effect among them are inade⁃*** this work,the effective mass in h-BN was successfully determined through a combined approach of ex⁃perimental and theoretical research methods by fitting the current-voltage curves of metal/insulator/metal struc⁃*** was observed that within a range of 4-22 layers,the effective mass of h-BN exhibits a monotonic de⁃crease with an increase in the number of *** physical parameters of the Fowler-Nordheim tunneling model in the context of electron tunneling in h-BN are precisely ascertained by utilizing the extracted effective ***⁃ditionally,the impact of fixed charges at the metal/h-BN interface and various metal electrode types on FowlerNordheim tunneling within this structure is investigated utilizing this physical parameter in Sentaurus TCAD soft⁃*** work is informative and instructive in promoting applications in the fields of h-BN related infrared physics and technology.