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Summary: Effect of operating temperature and film thickness on the pyroelectric
response of ferroelectric materials
A. Sharma, Z.-G. Ban, and S. P. Alpaya)
Department of Metallurgy and Materials Engineering and Institute of Materials Science,
University of Connecticut, Storrs, Connecticut 06269
J. V. Mantese
Delphi Research Laboratories, Shelby Township, Michigan 48315
Received 8 January 2004; accepted 21 April 2004; published online 28 May 2004
The influence of the operating temperature and film thickness on the pyroelectric properties of 001
Ba0.6Sr0.4TiO3 BST 60/40 epitaxial films on 001 LaAlO3 , MgO, and Si substrates is investigated
theoretically via a thermodynamic model. The results are presented using contour maps that can be
used to identify ``design windows'' for film thickness and operating temperature for optimum
pyroelectric response. For BST 60/40 on LAO and MgO large pyroelectric coefficients ( 0.7
C cm 2
K 1
) are observed at near room temperature for moderate film thickness 50200 nm .
The pyroresponse of films on Si is suppressed by two orders of magnitude compared to bulk BST
60/40 due to internal stresses. Significant recovery in the pyroelectric coefficient on Si is expected
for lower growth temperatures due to the reduction of thermal stresses. © 2004 American Institute
of Physics. DOI: 10.1063/1.1762691
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