The coupling effect of air-bridges on broadband spiral inductors in SiC-based MMIC technology

作     者：郑佳欣 马晓华 卢阳 赵博超 张恒爽 张濛 陈丽香 朱青 郝跃 

作者机构：School of Advanced Material and NanotechnologyXidian UniversityXi'an 710071China School of MicroelectronicsXidian UniversityXi'an 710071China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2017年第26卷第8期

页      面：529-535页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.61334002 and 61474091) the National High Technology Research and Development Program of China(Grant No.2015AA016801) 

主　　题：coupling effect air-bridge broadband spiral inductor exponential decay SiC MMIC 

摘      要：The coupling effect of air-bridges on broadband spiral inductors in SiC-based MMIC technology has been investigated deeply. The fabricated 1-nH spiral inductor on SiC substrate demonstrates a self-resonant frequency of 51.6 GHz, with a peak Q-fact of 12.14 at 22.1 GHz. From the S-parameters measurements, the exponential decay phenomenon is observed for L, Q-factor, and SRF with the air-bridge height decreasing, and an analytic expression is concluded to exactly fit the measured data which can be used to predict the performance of the spiral inductor. All the coefficients in the formula have specific meaning. By means of establishing the lumped model, the parasitic coupling capacitance of the air-bridge has been extracted and presents the exponential decay with the air-bridge heights decreasing which indicates that this capacitor is directly related to the coupling effect of the air-bridge. Through the electromagnetic field distribution simulation, the details of the electric field around the air-bridge have been presented which demonstrate the formation and the variation principles of the coupling effect.