Title :
A PMMA-based micro pressure sensor chip using carbon nanotubes as sensing elements
Author :
Fung, Carmen K M ; Zhang, Maggie Q H ; Chan, Rosa H M ; Li, Wen J.
Author_Institution :
Centre for Micro & Nano Syst., Chinese Univ. of Hong Kong, China
fDate :
30 Jan.-3 Feb. 2005
Abstract :
A polymer-based MEMS pressure sensor was fabricated using bulk multi-walled carbon nanotube (MWNT) as piezoresistive sensing elements. The development of the pressure sensor includes fabrication of 300μm thick polymethylmethacrylate (PMMA) diaphragms using SU8 molding/hot-embossing technique and AC electrophoretic manipulation of MWNT bundles on the diaphragms. We have measured the pressure-resistance dependency of these MWNT-based micro sensors and preliminary results indicated that the MWNT sensors were capable of sensing input pressure variations. Moreover, the I-V measurements of the resulting devices revealed that the nominal resistance of the sensing elements can be adjusted by annealing the MWNTs through electrical current heating, which offers a potential method for resistance-off set calibration. Based on these experimental evidences, we propose that carbon nanotubes (CNTs) is a novel material for fabricating micro pressure sensors on polymer substrates - which may serve as alternative sensors for silicon based pressure sensors when bio-compatibility and low-cost applications are required.
Keywords :
carbon nanotubes; microsensors; polymers; pressure sensors; 300 micron; AC electrophoretic manipulation; I-V measurements; MWNT-based micro sensors; PMMA-based micro pressure sensor chip; SU8 molding/hot-embossing technique; bio-compatibility applications; bulk multi-walled carbon nanotube; carbon nanotubes; electrical current heating; low-cost applications; piezoresistive sensing elements; polymer substrates; polymethylmethacrylate; pressure-resistance dependency; resistance-off set calibration; Biosensors; Carbon nanotubes; Chemical elements; Current measurement; Electrical resistance measurement; Fabrication; Micromechanical devices; Piezoresistance; Polymers; Pressure measurement;
Conference_Titel :
Micro Electro Mechanical Systems, 2005. MEMS 2005. 18th IEEE International Conference on
Print_ISBN :
0-7803-8732-5
DOI :
10.1109/MEMSYS.2005.1453914