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Displaying 51 - 75 of 98

Ultimate bending strength of Si nanowires

April 11, 2012
Author(s)
Gheorghe Stan, Sergiy Krylyuk, Albert Davydov, Igor Levin, Robert F. Cook
Test platforms for the ideal strength of materials are provided by almost defect-free nanostructures (nanowires, nanotubes, nanoparticles, for example). In this work, the ultimate bending strengths of Si nanowires with radii in the 20 nm to 60 nm range

Nanomechanical properties of polyethylene glycol brushes on gold substrates

February 15, 2012
Author(s)
Gheorghe NMN Stan, Frank W. DelRio, Robert I. MacCuspie, Robert F. Cook
Brushes of polyethylene glycol (PEG) were directly anchored onto bare gold substrates in solution. The nucleation kinetics of PEG binding were investigated successively in solution and dry air using atomic force microscopy (AFM) imaging. In addition, force

PROBING MATERIAL PROPERTIES WITH SHARP INDENTERS: A REVIEW

January 2, 2012
Author(s)
Brian R. Lawn, Robert F. Cook
A review on the use of sharp, fixed-profile indenters as materials probes is presented. Indentation is proposed as a simple but powerful methodology for evaluating basic mechanical properties—elastic modulus, hardness, toughness, etc.—in all classes of

Size Measurement of Nanoparticles Using Atomic Force Microscopy, ASTM E2859-11

January 2, 2012
Author(s)
Jaroslaw Grobelny, Frank W. DelRio, Pradeep Namboodiri, Doo-In Kim, Vincent A. Hackley, Robert F. Cook
The purpose of this document is to provide guidance on the quantitative application of atomic force microscopy (AFM) to determine the size of nanoparticles2 deposited in dry form on flat substrates using height (z-displacement) measurement. Unlike electron

Deformation and fracture of single-crystal silicon theta-like specimens

October 28, 2011
Author(s)
Michael S. Gaither, Frank W. DelRio, Richard S. Gates, Robert F. Cook
Miniaturized test specimens of single-crystal silicon, fabricated by lithography and deep reactive ion etching (DRIE), were used to measure deformation and fracture properties at the micro scale. Two specimen geometries, both in the form of a Greek letter

Micro-scale measurement and modeling of stress in silicon surrounding a tungsten-filled through-silicon via

October 11, 2011
Author(s)
Ryan P. Koseski, William Alexander Osborn, Stephan J. Stranick, Frank W. DelRio, Mark D. Vaudin, Thuy Dao, Vance H. Adams, Robert F. Cook
The stress in silicon surrounding a tungsten-filled through-silicon via (TSV) is measured using confocal Raman microscopy line scans across the TSV both before and after etch removal of an oxide stack used as a mask to define the TSV during fabrication

Prototype cantilevers for quantitative lateral force microscopy

September 27, 2011
Author(s)
Mark Reitsma, Richard S. Gates, Lawrence H. Friedman, Robert F. Cook
Prototype cantilevers that enable quantitative micro- to nano-scale surface force measurements using contact-mode atomic force microscopy (AFM) are presented. The “Hammerhead” cantilevers allow precise optical lever system calibrations for cantilever

Structure-property relationships for methyl-terminated alkyl self-assembled monolayers

July 20, 2011
Author(s)
Frank W. DelRio, Dave Rampulla, Cherno Jaye, Gheorghe Stan, Richard S. Gates, Daniel A. Fischer, Robert F. Cook
Structure-property relationships for methyl-terminated alkyl self-assembled monolayers (SAMs) are developed using near-edge X-ray absorption fine structure spectroscopy (NEXAFS) and atomic force microscopy (AFM). NEXAFS C K-edge spectra are used to compute

INDENTATION AND ADHESION AT SMALL LENGTH SCALES

June 1, 2011
Author(s)
Robert F. Cook
Indentation and adhesion are considered in the context of the two experimental methods predominantly used to measure contact behavior at small length scales, instrumented indentation testing and atomic force microscopy. The typical loads and displacements

MECHANICS OF ADHESION

June 1, 2011
Author(s)
Robert F. Cook
Abstract. A framework of increasing complexity is developed to describe the mechanics of adhesion and its reverse, de-adhesion or separation, during indentation contact cycles. The importance of the indentation probe stiffness in determination of system

Size Measurement of Nanoparticles using Atomic Force Microscopy

January 1, 2011
Author(s)
Jaroslaw Grobelny, Frank W. DelRio, Pradeep Namboodiri, Doo-In Kim, Vincent A. Hackley, Robert F. Cook
This chapter outlines procedures for sample preparation and the determination of nanoparticle size using atomic force microscopy (AFM). To start, procedures for dispersing gold nanoparticles on various surfaces such that they are suitable for imaging and

Measurement of residual stress field anisotropy at indentations in silicon

June 23, 2010
Author(s)
Yvonne B. Gerbig, Stephan J. Stranick, Robert F. Cook
The residual stress field around spherical indentations on single crystal silicon (Si) of different crystallographic orientation is mapped by confocal Raman microscopy. All orientations exhibit an anisotropic stress pattern with an orientation specific

Mechanical properties of one-dimensional nanostructures

May 23, 2010
Author(s)
Gheorghe Stan, Robert F. Cook
The elastic mechanical properties of one-dimensional nanostructures are considered, with an emphasis on the use of contact-resonance atomic force microscopy methods to determine elastic moduli. Various methods used to determine elastic moduli of one

Strength distribution of single-crystal silicon theta-like specimens

May 18, 2010
Author(s)
Michael S. Gaither, Frank W. DelRio, Richard S. Gates, Edwin R. Fuller, Robert F. Cook
A new test specimen has been developed for micro-scale tensile strength measurements, allowing direct assessment of surface effects on strength. Specimens were formed by deep reactive ion etching, tested with instrumented indentation, and test results

Probing the Nanoscale

April 23, 2010
Author(s)
Robert F. Cook
Nanoscale probes can now measure all manner of nanomechanical properties, opening up opportunities for new science and new devices.

Compressive stress effect on the radial elastic modulus of oxidized Si nanowires

March 23, 2010
Author(s)
Gheorghe Stan, Sergiy Krylyuk, Albert Davydov, Robert F. Cook
Detailed understanding and optimal control of the properties of Si nanowires are essential steps in developing Si nanoscale circuitry. In this work, we have investigated mechanical properties of as-grown and oxidized Si nanowires as a function of their

Theta-like specimen to determine tensile strength at the micro-scale

March 10, 2010
Author(s)
Michael S. Gaither, Frank W. DelRio, Richard S. Gates, Edwin R. Fuller, Robert F. Cook
Micro- and nano-electromechanical systems are typically formed via lithographic and etching processes that leave residual surface features, stresses, and chemistry that ultimately control component strength and device reliability. Here, we describe a new

The Nanomechanical Properties of Thin Film of Type I Collagen Fibrils

March 2, 2010
Author(s)
Koo-Hyun Chung, Kiran Bhadriraju, Tighe Spurlin, Robert F. Cook, Anne L. Plant
Cells sense and respond to the mechanical properties of the substrate to which they adhere. Matrices composed of collagen have been an important experimental system to study cell responses to the stiffness of the extracellular matrix. We had previously

Nanomechanical Measurements and Tools

February 23, 2010
Author(s)
Robert F. Cook
Nanotechnology provides great opportunities for the development of advanced devices with enormous quality-of-life and economic benefits, with applications ranging from biomedical implantable actuators to environmental toxin detectors to infrastructural