A passive wireless integrated humidity sensor

Author

Harpster, T.J. ; Stark, B. ; Najafi, K.

Author_Institution

Centre for Wireless Integrated Microsystems, Michigan Univ., Ann Arbor, MI, USA

fYear

2001

fDate

25-25 Jan. 2001

Firstpage

553

Lastpage

557

Abstract

This paper presents a single-chip integrated humidity sensor (IHS) capable of wireless operation through inductive coupling with a remote transmitter. The 1.5/spl times/0.5/spl times/8mm/sup 3/ sensor chip consists of a planar electroplated copper coil (20 /spl mu/m thick, 30 /spl mu/m pitch, and 23 turns) and a silicon substrate separated by a 4100-5600 /spl Aring/ polyimide film. The resonant frequency of the IHS changes with humidity and the measured sensitivity ranges from 4-16 kHz/%RH. Measurements show a hysteresis of 4.5%RH over a range of 30-70%RH for a 5600 /spl Aring/-thick polyimide film IHS.

Keywords

humidity sensors; microsensors; radiotelemetry; remote sensing; Cu; Si; hysteresis; inductive coupling; passive wireless integrated humidity sensor; planar electroplated copper coil; polyimide film; remote transmitter; resonant frequency; silicon substrate; single chip; Coils; Copper; Humidity; Polyimides; Semiconductor device measurement; Silicon; Substrates; Thick film sensors; Transmitters; Wireless sensor networks;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems, 2001. MEMS 2001. The 14th IEEE International Conference on

Conference_Location

Interlaken, Switzerland

ISSN

1084-6999

Print_ISBN

0-7803-5998-4

Type

conf

DOI

10.1109/MEMSYS.2001.906601

Filename

906601