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Porous Silica: A Potential Material for Low Dielectric Constant Applications

Published online by Cambridge University Press:  10 February 2011

Edward D. Birdsell  and
Rosario A. Gerhardt
Edward D. Birdsell
Affiliation:
Georgia Institute of Technology, School of Material Science and Engineering, Atlanta, GA
Rosario A. Gerhardt
Affiliation:
Georgia Institute of Technology, School of Material Science and Engineering, Atlanta, GA
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Abstract

Highly porous (15% dense) silica thin films with k < 2.2 have been produced using a colloidal sol-gel process. This process uses relatively inexpensive, commercially available colloidal silica and potassium silicate. These films were deposited by spin coating. The parameters for spin coating (spin speed, gelation time, gel composition, etc.) have been optimized and coherent films with thicknesses ranging from 0.7–2.0 μm can be reproducibly fabricated. Preliminary work shows that the porosity of these films ranges from a few rn to < 1 μm. The dielectric properties were examined for frequencies up to 1 MHz. Compatibility of the films with IC processing was also investigated.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 511: Symposium E – Low Dielectric Constant Materials IV , 1998 , 111
Copyright
Copyright © Materials Research Society 1998

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References

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