Ultrasonically Assisted Preparation of Carbon Fiber Doped Electriclly Conductive Micropatternable Nanocomposite Polymer for MEMS/Nems Applications
Authors: Basher Samiul , Sun He , Hirai Yuji , Sakai Kazuyuki , Yoshida Kazunari , Furukawa Hidemitsu , Sukumaran Sathish K. , Yoshida Tsukasa , Khosla Ajit 
Published: February 2020

Polymer MEMS/NEMS is a fast growing field with applications in lab on a chip (LOC), μTAS to new sensors and actuators to flexible micro-nano devices [1, 2,3]. While many polymers have been employed to realize flexible MEMS and microfluidic devices such as stated above, polydimethylsiloxane (PDMS), a silicone based elastomer, has been widely used because of its biocompatibility, low cost, low toxicity, high oxidative and thermal stability, optical transparent, low permeability to water, low electrical conductivity, and ease of micropatterning [4,5,6,7, 8]. However, most devices based on PDMS or any kind of polymers are passive and, if active devices are fabricated, then they are bonded to substrates like glass which may contain active components like electrodes, heaters etc patterned on glass. This is because it has proven difficult to integrate, embed or pattern conducting lines, magnetic materials on PDMS because of the weak adhesion between PDMS and metals/alloys. In order to over come this problem, in past we had demonstrated fabrication of various PDMS based micropatternable nanocomposite polymers which are either electrically conductive and magnetic in nature [9, 10, 11, 12].

In this work we present an improved electrically and thermally conducuctive micropatternable PDMS based nanocomposite polymer containg milled carbon fibers, prepared by ultrasonically assisted processing technology. The prepared nanocomposite not only shows a better electrical and thermal conductivity cpmpared to previpusly reported work [13, 14,15,16, 17], but also negative temerate cofficient of resistivity (NTCR), making them as an ideal candidate for on chip μ-temperature sensors.

Acknowledgements:

Authors would like to thank Nippon Graphite Fiber Co., Ltd, Japan; for proving milled carbon fiber and technical support for this project.

References:

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