Stress-induced orientation in chemical solution deposited tetragonal Lead Zirconate Titanate thin films

Author

Geoffrey L. Brennecka

Abstract

"The effect of stress from the substrate on the crystallographic orientation of tetragonal Lead Zirconate Titanate (PZT) thin films was investigated, and it was found that films under compressive stress during cooling through the Curie temperature (from being deposited on a substrate with a larger coefficient of thermal expansion (CTE) than PZT) tend to orient in thedirection. Conversely, films under tensile stress during processing due to a low-CTE substrate prefer (100) orientation.

While stress is important in determining eventual film texture, it is not the only factor. Platinum, the electrode of choice for most applications of PZT thin films, is most easily deposited with a (111) texture that provides a low-energy template for the subsequent nucleation and growth of (111) PZT. Films of different orientations, however, have been successfully deposited on (111) Pt, so the nucleation and growth of oriented PZT must not be completely electrode template controlled. Therefore solution, electrode texture, heat treatment, and stress effects on the orientation of tetragonal PZT films were also investigated.

A 5-minute crystallization step above 420°C produces PZT thin films with preferred (100) orientation, even on (111) Pt electrodes. Hot-sputtering Pt on (100) MgO single crystals can result in a (100) electrode texture, which favors film growth along one of the cubic directions, or . Films oriented in the direction were found to have P_r values as high as 46µC/cm² and effective d₃₁ values as large as -57pm/V. Films oriented along the direction had respective P_r and effective d₃₁ values of only 27µC/cm² and -37pm/V. Measured dielectric constants followed the opposite trend, with values 800 and 425 for virgin films oriented in the and directions, respectively"--Abstract, page iii.

Advisor(s)

Huebner, Wayne

Committee Member(s)

Anderson, H. U. (Harlan U.)
Clem, Paul G.
Schwartz, Robert W.

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Ceramic Engineering

Publisher

University of Missouri--Rolla

Publication Date

Fall 2002

Pagination

xii, 89 pages

Note about bibliography

Includes bibliographical references (pages 74-88).

Rights

© 2002 Geoffrey Lee Brennecka, All rights reserved.

Document Type

Thesis - Restricted Access

File Type

text

Language

English

Thesis Number

T 8093

Print OCLC #

51220054

Recommended Citation

Brennecka, Geoffrey L., "Stress-induced orientation in chemical solution deposited tetragonal Lead Zirconate Titanate thin films" (2002). Masters Theses. 2171.
https://scholarsmine.mst.edu/masters_theses/2171