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Title: Mechanical characterization of solution-derived nanoparticle silver ink thin films

Abstract

Mechanical properties of sintered silver nanoparticles are investigated via substrate curvature and nanoindentation methods. Substrate curvature measurements reveal that permanent microstructural changes occur during initial heating while subsequent annealing results in nearly elastic behavior of the thinner films. Thicker films were found to crack upon thermal treatment. The coefficient of thermal expansion was determined from linear slopes of curvature curves to be 1.9{+-}0.097 ppm/ degree sign C, with elastic modulus and hardness determined via nanoindentation. Accounting for substrate effects, nanoindentation hardness and modulus remained constant for different film thicknesses and did not appear to be a function of annealing conditions. Hardness of 0.91 GPa and modulus of 110 GPa are somewhat lower than expected for a continuous nanocrystalline silver film, most likely due to porosity.

Authors:
;  [1]
  1. Palo Alto Research Center (PARC), 3333 Coyote Hill Road, Palo Alto, California 94304 (United States)
Publication Date:
OSTI Identifier:
20982891
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 10; Other Information: DOI: 10.1063/1.2735404; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; CRACKS; ELASTICITY; HARDNESS; HEATING; INKS; MICROSTRUCTURE; NANOSTRUCTURES; PARTICLES; POROSITY; PRESSURE RANGE GIGA PA; SILVER; SOLUTIONS; SUBSTRATES; THERMAL EXPANSION; THIN FILMS

Citation Formats

Greer, Julia R., and Street, Robert A.. Mechanical characterization of solution-derived nanoparticle silver ink thin films. United States: N. p., 2007. Web. doi:10.1063/1.2735404.
Greer, Julia R., & Street, Robert A.. Mechanical characterization of solution-derived nanoparticle silver ink thin films. United States. doi:10.1063/1.2735404.
Greer, Julia R., and Street, Robert A.. Tue . "Mechanical characterization of solution-derived nanoparticle silver ink thin films". United States. doi:10.1063/1.2735404.
@article{osti_20982891,
title = {Mechanical characterization of solution-derived nanoparticle silver ink thin films},
author = {Greer, Julia R. and Street, Robert A.},
abstractNote = {Mechanical properties of sintered silver nanoparticles are investigated via substrate curvature and nanoindentation methods. Substrate curvature measurements reveal that permanent microstructural changes occur during initial heating while subsequent annealing results in nearly elastic behavior of the thinner films. Thicker films were found to crack upon thermal treatment. The coefficient of thermal expansion was determined from linear slopes of curvature curves to be 1.9{+-}0.097 ppm/ degree sign C, with elastic modulus and hardness determined via nanoindentation. Accounting for substrate effects, nanoindentation hardness and modulus remained constant for different film thicknesses and did not appear to be a function of annealing conditions. Hardness of 0.91 GPa and modulus of 110 GPa are somewhat lower than expected for a continuous nanocrystalline silver film, most likely due to porosity.},
doi = {10.1063/1.2735404},
journal = {Journal of Applied Physics},
number = 10,
volume = 101,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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