Fabrication of 3D air-core MEMS inductors for very-highfrequency power conversions  

作　　者：Hoa Thanh Le Io Mizushima Yasser Nour Peter Torben Tang Arnold Knott Ziwei Ouyang Flemming Jensen Anpan Han 

机构地区：[1]National Center for Micro-and Nanofabrication,Danchip,Technical University of Denmark,2800 Kongens Lyngby,Denmark [2]Department of Electrical Engineering,Technical University of Denmark,2800 Kongens Lyngby,Denmark [3]IPU,Nils Koppels Allé,2800 Kongens Lyngby,Denmark

出　　处：《Microsystems & Nanoengineering》2018年第1期509-517,共9页微系统与纳米工程（英文）

基　　金：This project is a part of the TinyPower project,which is funded by the Innovation Foundation(No.67-2014-1).

摘　　要：We report a fabrication technology for 3D air-core inductors for small footprint and very-high-frequency power conversions.Our process is scalable and highly generic for fabricating inductors with a wide range of geometries and core shapes.We demonstrate spiral,solenoid,and toroidal inductors,a toroidal transformer and inductor with advanced geometries that cannot be produced by wire winding technology.The inductors are embedded in a silicon substrate and consist of through-silicon vias and suspended windings.The inductors fabricated with 20 and 25 turns and 280-350μm heights on 4-16 mm2 footprints have an inductance from 34.2 to 44.6 nH and a quality factor from 10 to 13 at frequencies ranging from 30 to 72 MHz.The air-core inductors show threefold lower parasitic capacitance and up to a 140% higher-quality factor and a 230% higher-operation frequency than silicon-core inductors.A 33 MHz boost converter mounted with an air-core toroidal inductor achieves an efficiency of 68.2%,which is better than converters mounted with a Si-core inductor(64.1%).Our inductors show good thermal cycling stability,and they are mechanically stable after vibration and 2-m-drop tests.

关 键 词：MEMS inductor PwrSoC TSVs very high frequency 3D 

分 类 号：TL6[核科学技术—核技术及应用]