Development of an automated microspotting system for rapid dielectrophoretic fabrication of bundled carbon nanotube sensors

An automated carbon nanotube (CNT) microspotting system was developed for rapid and batch assembly of bulk multiwalled carbon nanotubes (MWNTs)-based microelectromechanical system sensors. By using the dielectrophoretic and microspotting technique, MWNT bundles were successfully and repeatedly manipulated between an array of microfabricated electrodes. Preliminary experimental results showed that more than 75% of CNT functional devices can be assembled successfully using our technique, which is considered to be a good yield for nanodevice manufacturing. Besides, the devices were demonstrated to potentially serve as novel thermal sensors for temperature and fluid-flow measurements. This feasible batch manufacturable method will dramatically reduce production costs and production time of nanosensing devices and potentially enable fully automated assembly of CNT-based devices. Note to Practitioners-This paper was motivated by the problem of manipulate carbon naotube (CNT) across gold microelectrodes effectively and precisely. The purposed system potentially applies to other nano-sized particles that are neutral and with high polarizability. Existing methods of CNT assembly include guided CNT growth, external forces, polar molecular patterning, and atomic force microscopy (AFM) manipulation, which is time-consuming and unrealistic when considering batch production of CNT-based sensors. This paper reported a novel method to build CNT-based sensors across the microelectrodes by using our automated microspotting system. This system is integrated with a dielectrophoretic and microspotting technique. We first explained the dielectrophorectic effect on CNT-this method is very effective to manipulate CNT. Then, the microspotting technique was developed to spot a micron-sized CNT dilution droplet on the desired positions of a microchip substrate. Finally, dielectropheretic manipulation can be used to position CNT bundles across the microelectrodes. In this paper, we experimentally showed the difficulties to spot a micron-sized droplet, and the problems can be overcome by sharpening the spotting probe chemically and using the special spotting method. We then show the yield of CNT-based sensors fabricated by using this system is very promising. We also reported that the CNT-based sensors have low power consumption, and CNT can be used as the sensing element of the thermal sensor. The experimental results indicated this approach is feasible to develop batch manufacturing of nano devices.

[1]  J. Tersoff Contact resistance of carbon nanotubes , 1999 .

[2]  H. Lezec,et al.  Electrical conductivity of individual carbon nanotubes , 1996, Nature.

[3]  P. Ajayan,et al.  Microfabrication technology: Organized assembly of carbon nanotubes , 2002, Nature.

[4]  U. Kaatze,et al.  Water−Ethanol Mixtures at Different Compositions and Temperatures. A Dieletric Relaxation Study , 2000 .

[5]  Christoph Strunk,et al.  Contacting carbon nanotubes selectively with low-ohmic contacts for four-probe electric measurements , 1998 .

[6]  Seiji Akita,et al.  Orientation of Carbon Nanotubes Using Electrophoresis , 1996 .

[7]  H. A. Pohl,et al.  Dielectrophoresis: The Behavior of Neutral Matter in Nonuniform Electric Fields , 1978 .

[8]  Wim Rutten,et al.  Understanding dielectrophoretic trapping of neuronal cells: modelling electric field, electrode-liquid interface and fluid flow , 2002 .

[9]  K. G. Ong,et al.  Effect of purification of the electrical conductivity and complex permittivity of multiwall carbon nanotubes , 2001 .

[10]  R. Krupke,et al.  Separation of Metallic from Semiconducting Single-Walled Carbon Nanotubes , 2003, Science.

[11]  R. Smalley,et al.  Magnetically aligned single wall carbon nanotube films: preferred orientation and anisotropic transport properties , 2003 .

[12]  Wen J. Li,et al.  DEPENDENCE OF AC ELECTROPHORESIS CARBON NANOTUBE MANIPULATION ON MICROELECTRODE GEOMETRY , 2002 .

[13]  Charles M. Lieber,et al.  Nanobeam Mechanics: Elasticity, Strength, and Toughness of Nanorods and Nanotubes , 1997 .

[14]  K. Ishibashi,et al.  Nanostructure construction in single-walled carbon nanotubes by AFM manipulation , 2001, Digest of Papers. Microprocesses and Nanotechnology 2001. 2001 International Microprocesses and Nanotechnology Conference (IEEE Cat. No.01EX468).

[15]  D. Austin,et al.  The electrodeposition of metal at metal/carbon nanotube junctions , 2002 .

[16]  P. Ajayan,et al.  Reliability and current carrying capacity of carbon nanotubes , 2001 .

[17]  S. Roche,et al.  Batch processing of nanometer-scale electrical circuitry based on in-situ grown single-walled carbon nanotubes , 2002 .

[18]  Tarek El-Aguizy,et al.  Large-Scale Assembly of Carbon Nanotubes , 2004 .

[19]  H. Morgan,et al.  Ac electrokinetics: a review of forces in microelectrode structures , 1998 .

[20]  Seiji Akita,et al.  RAPID COMMUNICATION: Orientation and purification of carbon nanotubes using ac electrophoresis , 1998 .

[21]  S. Iijima Helical microtubules of graphitic carbon , 1991, Nature.

[22]  King Wai Chiu Lai,et al.  KL probes for robotic-based cellular nano surgery , 2003, 2003 Third IEEE Conference on Nanotechnology, 2003. IEEE-NANO 2003..

[23]  C. Hsu,et al.  Mechanical stability and adhesion of microstructures under capillary forces. I. Basic theory , 1993 .

[24]  Chih-Ming Ho,et al.  Fluidic shear-stress measurement using surface-micromachined sensors , 1995, 1995 IEEE TENCON. IEEE Region 10 International Conference on Microelectronics and VLSI. 'Asia-Pacific Microelectronics 2000'. Proceedings.

[25]  Thomas B. Jones,et al.  Electromechanics of Particles , 1995 .

[26]  Jiangtao Hu,et al.  Controlled growth and electrical properties of heterojunctions of carbon nanotubes and silicon nanowires , 1999, Nature.

[27]  Zhong Lin Wang,et al.  Carbon nanotube quantum resistors , 1998, Science.

[28]  Wahyu Setyawan,et al.  Nanotube electronics: Large-scale assembly of carbon nanotubes , 2003, Nature.

[29]  Rosa H. M. Chan,et al.  Rapid assembly of carbon nanotubes for nanosensing by dielectrophoretic force , 2004 .

[30]  Chih-Ming Ho,et al.  A micro-electro-mechanical-system-based thermal shear-stress sensor with self-frequency compensation , 1999 .

[31]  K. Gamo,et al.  Contact resistance of multiwall carbon nanotubes , 2003 .

[32]  Chih-Ming Ho,et al.  A micromachined flow shear-stress sensor based on thermal transfer principles , 1999 .

[33]  Charles M. Lieber,et al.  Directed assembly of one-dimensional nanostructures into functional networks. , 2001, Science.

[34]  Jinhee Kim,et al.  Formation of low-resistance ohmic contacts between carbon nanotube and metal electrodes by a rapid thermal annealing method , 2000 .

[35]  P. Avouris,et al.  Engineering Carbon Nanotubes and Nanotube Circuits Using Electrical Breakdown , 2001, Science.