Gheorghe Stan and Robert F. Cook


In today’s exploration of the nanoworld, investigation of mechanical properties at the nanoscale has become a necessity. Either in nanolectronics or nanoelectromechanical systems, mechanical property characterization of the constituent building blocks in the form of ultrathin films and one-dimensional nanostructures (nanotubes, nanowires, nanobelts, etc) is a necessary step for their assembly and functionality. It is thus imperative to develop techniques capable of providing easy and reliable mechanical property measurements at the nanoscale.  Benefiting from the nanoscale spatial resolution of atomic force microscopy, contact-resonance atomic force microscopy (CR-AFM) provides direct measurements of the elastic responses of materials at the nanoscale. In the past few years, we have improved and developed the capabilities of CR-AFM in various ways: established clear criteria for assessing the precision and accuracy in CR-AFM measurements [1], introduced a load-dependent CR-AFM protocol suitable for elastic modulus measurements on compliant materials, and tested the suitability of CR-AFM measurements across materials with elastic moduli in the range of GPa to hundreds of GPa. We have also extended the CR-AFM applicability to quantitative elastic modulus measurements on various one-dimensional nanostructures (nanowires [2, 3] and nanotubes [4]). Another valuable CR-AFM application was the interrogation of elastic properties at the nanoscale on granular nanocrystalline surfaces [5] and low-k dielectric films [6]. All these CR-AFM developments enable current and future nanotechnology applications.   


[1] G. Stan and W. Price, Rev. Sci. Instrum. 77, 103707 (2006).

[2] G. Stan, C. V. Ciobanu, P. M. Parthangal, and R. F. Cook, Nano Lett. 7, 3691 (2007).

[3] G. Stan, S. Krylyuk, A. V. Davydov, M. Vaudin, L. A. Bendersky, and R. F. Cook, Appl. Phys. Lett. 92, 241908 (2008).

[4] G. Stan, C. V. Ciobanu, T. P. Thayer, G. T. Wang, R. J. Creighton, K. P. Purushotham, L. A. Bendersky, and R. F. Cook, Nanotechnology 20, 035706 (2009).

[5] G. Stan and R. F. Cook, Nanotechnology 19, 235701 (2008).

[6] G. Stan, S. King, and R. F. Cook (to be submitted).













Author Information:

Name:                           Gheorghe Stan

Mentor’s name:            Robert F. Cook

Division:                       Ceramics, 852

Laboratory:                   MSEL

Room/Building:            B107/217

Mail Stop:                     8526

Telephone #:                 301-975-3675

Fax #:                            301-975-5995


Sigma Xi:                      not a member

Category:                       Materials