Finite Element Model of a Bilayered Gold-Coated Carbon Nanotube Composite Surface

Vertically aligned multiwalled carbon nanotubes (MWCNTs), with a gold (Au)-coated surface, have been shown to provide a stable contact resistance for electrical contact switching applications under low force conditions (micronewton to millinewton), with the MWCNT surface providing a compliant support for the conducting Au layer. In this paper, nanoindentation results are used in the development of a finite element contact model for the composite, referred to as Au/CNT. The results show that the surface is best modeled as a bilayered structure, in which the top layer is modeled as an elastic-plastic layer of the Au/CNT mixed material and the under layer as a CNT forest. The resultant model matches the experimental results for a range of samples with different thickness configurations.

[1]  J. McBride,et al.  Mechanical characterization of a Au coated carbon nanotube multi-layered structure , 2014, 2014 IEEE 60th Holm Conference on Electrical Contacts (Holm).

[2]  J. W. McBride,et al.  Evaluating the Influence of Current on the Wear Processes of Au/Cr-Au/MWCNT Switching Surfaces , 2013, 2013 IEEE 59th Holm Conference on Electrical Contacts (Holm 2013).

[3]  J. McBride,et al.  A review of micro-contact physics for microelectromechanical systems (MEMS) metal contact switches , 2013 .

[4]  Chamaporn Chianrabutra,et al.  The Contact Resistance Performance of Gold Coated Carbon-Nanotube Surfaces under Low Current Switching , 2012, IEICE Trans. Electron..

[5]  P. Pons,et al.  Finite Element Based Surface Roughness Study for Ohmic Contact of Microswitches , 2012, 2012 IEEE 58th Holm Conference on Electrical Contacts (Holm).

[6]  K. Goodson,et al.  Impact of nanotube density and alignment on the elastic modulus near the top and base surfaces of aligned multi-walled carbon nanotube films , 2012 .

[7]  Thomas W. Kenny,et al.  Mechanical characterization of aligned multi-walled carbon nanotube films using microfabricated resonators , 2012 .

[8]  A. Slocum,et al.  Compliant Carbon Nanotube-Metal Contact Structures , 2011, 2011 IEEE 57th Holm Conference on Electrical Contacts (Holm).

[9]  S. Spearing,et al.  Gold Coated Carbon-Nanotube Surfaces as Low Force Electrical Contacts for MEMS Devices: Part II, Fine Transfer Mechanisms , 2011, 2011 IEEE 57th Holm Conference on Electrical Contacts (Holm).

[10]  Qiuhong Zhang,et al.  Length dependent foam-like mechanical response of axially indented vertically oriented carbon nanotube arrays , 2011 .

[11]  R. Plana,et al.  Multi-Physical Characterization of Micro-Contact Materials for MEMS Switches , 2010, 2010 Proceedings of the 56th IEEE Holm Conference on Electrical Contacts.

[12]  E. M. Yunus,et al.  Improving the contact resistance at low force using gold coated carbon nanotube surfaces , 2010 .

[13]  J. Oberhammer,et al.  A Ruthenium-Based Multimetal-Contact RF MEMS Switch With a Corrugated Diaphragm , 2008, Journal of Microelectromechanical Systems.

[14]  K. Baynes,et al.  Hemispheric asymmetries in the perceptual representations of words , 2008, Brain Research.

[15]  M. Oliveira,et al.  On the determination of the young's modulus of thin films using indentation tests , 2007 .

[16]  E. M. Yunus,et al.  The Relationship between Contact Resistance and Contact Force on Au coated Carbon Nanotube surfaces , 2007, Electrical Contacts - 2007 Proceedings of the 53rd IEEE Holm Conference on Electrical Contacts.

[17]  J. R. Reid,et al.  Microswitches with sputtered Au, AuPd,Au-on-AuPt, and AuPtCu alloy electric contacts , 2006, IEEE Transactions on Components and Packaging Technologies.

[18]  Mehrdad N. Ghasemi-Nejhad,et al.  Super‐Compressible Foamlike Carbon Nanotube Films. , 2006 .

[19]  G. Pharr,et al.  Measurement of hardness and elastic modulus by instrumented indentation: Advances in understanding and refinements to methodology , 2004 .

[20]  R. Ruoff,et al.  Mechanical properties of carbon nanotubes: theoretical predictions and experimental measurements , 2003 .

[21]  J. Robertson,et al.  Determination of mechanical properties of carbon nanotubes and vertically aligned carbon nanotube forests using nanoindentation , 2003 .

[22]  L. Kogut,et al.  Elastic-Plastic Contact Analysis of a Sphere and a Rigid Flat , 2002 .

[23]  Frank T. Fisher,et al.  Effects of nanotube waviness on the modulus of nanotube-reinforced polymers , 2002 .

[24]  William D. Nix,et al.  Effects of the substrate on the determination of thin film mechanical properties by nanoindentation , 2002 .

[25]  Bharat Bhushan,et al.  A Numerical Three-Dimensional Model for the Contact of Layered Elastic/Plastic Solids With Rough Surfaces by a Variational Principle , 2001 .

[26]  A. Kulik,et al.  Mechanical properties of carbon nanotubes , 1999 .

[27]  D. Munz,et al.  Determination of elastic modulus of thin layers using nanoindentation , 1997 .

[28]  G. Pharr,et al.  An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments , 1992 .

[29]  William D. Nix,et al.  A method for interpreting the data from depth-sensing indentation instruments , 1986 .

[30]  S. Sitaraman,et al.  Waviness reduces effective modulus of carbon nanotube forests by several orders of magnitude , 2014 .

[31]  E. M. Yunus,et al.  Investigation of gold sputter coated vertically aligned multi-walled carbon nanotubes for RF MEMS contact surfaces. , 2008 .

[32]  P. Avouris,et al.  Mechanical Properties of Carbon Nanotubes , 2001 .

[33]  Huajian Gao,et al.  Elastic contact versus indentation modeling of multi-layered materials , 1992 .

[34]  W. Nix,et al.  Analysis of elastic and plastic deformation associated with indentation testing of thin films on substrates , 1988 .

[35]  R. King,et al.  Elastic analysis of some punch problems for a layered medium , 1987 .