Effect of organometallic clamp properties on the apparent diversity of tensile response of nanowires

• Published in: Nanotechnology 2013-06, Vol.24 (23), p.235704-235704
• Main Authors: Murphy, Kathryn F, Chen, Lisa Y, Gianola, Daniel S
• Format: Article
• Language: English
• Subjects: Clamping; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Materials selection; Mechanical and acoustical properties of condensed matter; Mechanical properties; Mechanical properties of nanoscale materials; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanowires; Physics; Quantum wires; Scanning electron microscopy; Strain; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/0957-4484/24/23/235704

The influence of the experimental boundary conditions used for tensile testing of individual nanowires on the measured apparent mechanical response is reported. Using a microelectromechanical platform designed for in situ tensile testing, in combination with digital image correlation of sequences of scanning electron microscope images, the mechanical behavior of single crystalline Si, Pd, and Ge2Sb2Te5 nanowires was measured during load-unload cycles. In situ testing enables direct determination of the nanowire strain. Comparison of the direct strain with common metrics for apparent strain that include any compliance or slipping of the clamping materials (electron-beam induced Pt-containing deposits) highlights several different artifacts that may be manifested. Calculation of the contact stiffness is thus enabled, providing guidelines for both proper strain measurement and selection of clamping materials and geometries that facilitate elucidation of intrinsic material response. Our results suggest that the limited ability to tailor the stiffness of electron-beam induced deposits results from the predominance of the organic matrix in controlling its mechanical properties owing to relatively low Pt content and sparse morphology.