A Tunable RF MEMS Inductor on Silicon Incorporating an Amorphous Silicon Bimorph in a Low-Temperature Process

A novel tunable radio frequency microelectromechanical system inductor based on the bimorph effect of an amorphous silicon (a-Si) and aluminum structural layer is presented. The outer turns of the inductor have a vertical height of 450 mum when no voltage is applied. A 32% tuning range with high inductance (5.6-8.2 nH) is achieved by the application of a voltage, with the structure completely flattening at 2 V. With no actuation, the peak quality factor is 15, and the self-resonance frequency is 7 GHz. The fact that the device is fabricated on Si in a low-temperature (150 degC) process enhances the potential for system integration

[1]  David K. Fork,et al.  Out-of-plane high-Q inductors on low-resistance silicon , 2003 .

[2]  J. Leclercq,et al.  Micromachined microwave planar spiral inductors and transformers , 2000 .

[3]  Hongrui Jiang,et al.  On-chip spiral inductors suspended over deep copper-lined cavities , 2000 .

[4]  Michal Okoniewski,et al.  Tunable radio frequency MEMS inductors with thermal bimorph actuators , 2005 .

[5]  M. Allen,et al.  High O spiral-type microinductors on silicon substrates , 1999, IEEE International Magnetics Conference.

[6]  Y.C. Liang,et al.  A concise process technology for 3-D suspended radio frequency micro-inductors on silicon substrate , 2002, IEEE Electron Device Letters.

[7]  V. Lubecke,et al.  Self-assembling MEMS variable and fixed RF inductors , 2000, 2000 Asia-Pacific Microwave Conference. Proceedings (Cat. No.00TH8522).

[8]  Jose E. Schutt-Aine,et al.  Development of three-dimensional inductors using plastic deformation magnetic assembly (PDMA) , 2003 .

[9]  S. Wong,et al.  Physical modeling of spiral inductors on silicon , 2000 .

[10]  G. Fischer,et al.  RF MEMS for ubiquitous wireless connectivity. Part I. Fabrication , 2004, IEEE Microwave Magazine.

[11]  S. Sivoththaman,et al.  Development of a low temperature MEMS process with a PECVD amorphous silicon structural layer , 2006 .

[12]  E. Yoon,et al.  CMOS-compatible surface-micromachined suspended-spiral inductors for multi-GHz silicon RF ICs , 2002 .

[13]  F. Ayazi,et al.  A low cost wafer-level MEMS packaging technology , 2005, 18th IEEE International Conference on Micro Electro Mechanical Systems, 2005. MEMS 2005..

[14]  Xi-Qing Sun,et al.  A monolithic variable inductor network using microrelays with combined thermal and electrostatic actuation , 1999 .

[16]  H.J. De Los Santos,et al.  RF MEMS for ubiquitous wireless connectivity. Part II. Application , 2004, IEEE Microwave Magazine.

[17]  E. Yeatman,et al.  High Q microwave inductors on silicon by surface tension self-assembly , 2000 .