A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip transformers is proposed. A novel de-coupling technique is first developed to reduce the complexity in the Y parameters for the transformer, and the model parameters can then be extracted analytically by a set of characteristic functions. Simulation based on the extracted parameters has been carried out for transformers with different structures, and good accuracy is obtained compared to a 3-demensional full-wave numerical electro- magnetic field solver. The presented approach will be very useful to provide a scalable and wide-band compact circuit model for Si-based RF transformers.
重点研究了聚焦离子束的相关原理和应用。利用聚焦离子束应力引入致形变(Focused Ion Beam Stress-Introduced Deformation,FIB-SID)技术与常规微加工工艺相结合,制备微型金属无源螺旋电感的设计方法和工艺流程,并对其电学性能进行初步高频测试。首先在SOI(Silicon-on-Insulator)基片上通过光刻、溅射以及各项同性刻蚀等常规工艺制得悬浮的金属悬臂梁,再利用FIB刻蚀原理进行应力引入,通过控制注入离子剂量、FIB应力引入的次数、FIB扫描的间距等试验参数制得不同尺寸结构的三维螺旋金属无源电感。后,采用安捷伦网络分析仪与微波探针台,使用GSG结构及相应的去嵌方法,对微型金属螺线管电感进行了高频测试。得出了三维螺旋微纳电感的电感值、品质因子、电压驻波比、回波损耗随频率变化关系。
This paper presents three compact ultra-wideband(UWB)antennas fed by coplanar waveguide(CPW).The proposed antennas consist of a planar circular patch monopole UWB antenna and multiple etched slots on the feed line.Simulation by Ansoft high frequency structure simulator(HFSS)10.0 shows that the in-band impedances are quite stable and satisfactory.Rejected narrow frequency bands are further obtained within the wideband width by inserting U-shaped slots into the fed line of the antennas.The antennas have a dimension of 50mm by 40mm by 1.5mm.The simulation and measurement results show that the proposed antennas have stable directional radiation patterns,very low profile and low fabrication cost,which are suitable for the UWB system.
