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Processing and Characterization of High Porosity Aerogel Films

Published online by Cambridge University Press:  28 February 2011

Lawrence W. Hrubesh  and
John F. Poco
Lawrence W. Hrubesh
Affiliation:
Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48 Chemistry and Material Science Department, Lawrence Livermore National Laboratory, Box 808, Livermore, California 94550
John F. Poco
Affiliation:
Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48 Chemistry and Material Science Department, Lawrence Livermore National Laboratory, Box 808, Livermore, California 94550
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Abstract

Aerogels are highly porous solids having unique morphology among materials because both the pores and particles making up the material have sizes less than wavelengths of visible light. Such a unique morphology modifies the normal molecular transport mechanisms within the material, resulting in exceptional thermal, acoustical, mechanical, and electrical properties. For example, aerogels have the lowest measured thermal conductivity and dielectric constant for any solid material. Special methods are required to make aerogel films with high porosity. In this paper, we discuss the special conditions needed to fabricate aerogel films having porosities greater than 75% and we describe methods of processing inorganic aerogel films having controllable thicknesses in the range 0.5 to 200 micrometers. We report methods and results of characterizing the films including thickness, refractive index, density (porosity), and dielectric constant. We also discuss results of metallization and patterning on the aerogel films for applications involving microminiature electronics and thermal detectors.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 371: Symposium W1 – Advances in Porous Materials , 1994 , 195
Copyright
Copyright © Materials Research Society 1995

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