J. Jones—contributing editor
Spin Spray-Deposited Nickel Manganite Thermistor Films For Microbolometer Applications
Article first published online: 29 SEP 2010
© 2010 The American Ceramic Society
Journal of the American Ceramic Society
Volume 94, Issue 2, pages 516–523, February 2011
How to Cite
Ko, S. W., Li, J., Podraza, N. J., Dickey, E. C. and Trolier-McKinstry, S. (2011), Spin Spray-Deposited Nickel Manganite Thermistor Films For Microbolometer Applications. Journal of the American Ceramic Society, 94: 516–523. doi: 10.1111/j.1551-2916.2010.04097.x
Research was sponsored by the U.S. Army Research Office and U.S. Army Research Laboratory and was accomplished under Cooperative Agreement Number W911NF-0-2-0026.
- Issue published online: 7 FEB 2011
- Article first published online: 29 SEP 2010
- Manuscript No. 27858. Received April 14, 2010; approved July 29, 2010.
Nickel manganite thin films are good candidates for thermal imaging applications because of their large temperature coefficient of resistance (TCR), (>−3%/K) and good environmental stability. To enable low-temperature deposition (90°C) on preexisting circuitry, a spin spray technique was developed for these materials. As-deposited manganese oxide films show well-developed X-ray diffraction patterns, while as-deposited nickel manganite films exhibit a nanocrystalline spinel structure. Low-temperature (400°C) postdeposition annealing leads to densification of the nanocrystalline nickel manganite spinel films. Spectroscopic ellipsometry measurements on annealed films provide complex dielectric function spectra over a range from 0.75 to 5.15 eV with comparable features with those found in films prepared by a chemical solution method. Energy-dispersive X-ray spectroscopy indicates that the final composition of the films is Ni deficient relative to the starting solution composition. The TCR of the nickel manganite films annealed at 400°C in an argon atmosphere is −3.6%/K. Doping the nickel manganite films with zinc results in an improvement of crystallinity, but leads to substantial increases in the electrical resistivity. Copper doping reduces the resistivity of the films to <1.0 kΩ·cm without degrading the crystalline quality, thus resulting in films suitable for microbolometer applications.