Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T02:06:58.015Z Has data issue: false hasContentIssue false
  • English
  • Français

Multilayer Coatings and Optical Materials for Tuned Infrared Emittance and Thermal Control

Published online by Cambridge University Press:  10 February 2011

P. M. Martin ,
J. W. Johnston  and
W. D. Bennett
P. M. Martin
Affiliation:
Pacific Northwest National Laboratory, POBox 999, Richland, WA 99352, [email protected]
J. W. Johnston
Affiliation:
Pacific Northwest National Laboratory, POBox 999, Richland, WA 99352, [email protected]
W. D. Bennett
Affiliation:
Pacific Northwest National Laboratory, POBox 999, Richland, WA 99352, [email protected]
Get access

Abstract

Many thermal control applications require thin film coatings that emit or absorb strongly at near infrared and infrared wavelengths. One of the primary applications for these coatings is thermal control for surfaces and structures of spacecraft, which are exposed to solar radiation during at least 60% of their orbit, causing wide temperature fluctuations. Another recent application for this type of coating is infrared emissive imaging employing a fiber optic infrared scene projector. While single layer coatings can provide high emissivity in a broad wavelength band, multilayer coatings can be used to obtain higher emissivities over a narrow wavelength band. This band can be tuned to a specific range of temperatures and wavelengths. Coatings developed for thermal control have a reflective base layer, either ZrN or a refractory metal boride or silicide. These materials have increased durability compared to metal layers. The multilayer coating deposited over the based layer consists of an A1203/SiO2 stack with high emittance at 300 K (9.8 μm), and solar reflectance near 0.6. Multilayer tuned infrared absorber/emitter coatings are applied to fiber optic infrared scene projectors. The coatings consists of a three layer Si3N4/Cr/Si3N4 absorber tuned at the 1.06 μtm laser wavelength, and a six layer Cr/dielectric/Cr/dielectric/Cr/dielectric coating which emits strongly in either the 3 - 5 jim or the 8 - 12 μm infrared wavelength bands. Absorption bands of the coatings are independently tunable. All coatings are deposited by reactive DC and RF magnetron sputtering onto 2.5-in fiber optic faceplates. Either Si3N4, Si, or ZnS thin film dielectric materials were used in the emitter coatings. With an input laser power of 15 W, the coatings emit at a black body temperature 529 K, which compared well with predicted performance.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 555: Symposium OO – Properties and Processing of Vapor-Deposited Coatings , 1998 , 3
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Olalde, G., Flamant, G., Schwander, D., “Advanced high temperature semitransparent solar absorbers”, SPIE Proceedings Vol.502, p 77, 1984.Google Scholar
2. Ritchie, I., Kittler, W. C., Jr., , Andus, “Selective radiation shielding and solar control applications of multilayer metal and dielectric coatings”, SPIE Proceedings Vol.823, p 2, 1987.Google Scholar
3. Bly, V. T. and Cox, J. T, “Infrared Absorber for Ferroelectric Detectors”, Applied Optics, 33 No. 1, January 1994, p 26.Google Scholar
4. Dalbey, R. C., “Fiber Optic Scene Projector”, to appear in Proceedings of the International Conference on Metallurgical Coatings and Thin Films 1998, San Diego, CA, April 27 - May 1, 199.Google Scholar
5. Herzenberg, S. A. and Silberglitt, R., “Low temperature selective absorber research”, SPIE Proceedings Vol.324, 1982, p 92.Google Scholar
6. Handbook of Optics, Vol 2, Bass, M., ed., , McGraw Hill, New York, 1995, p 25.8.Google Scholar
7. Donnadieu, A. and Ezbakhe, H., “Effect of roughness on the selectivity of absorbing surfaces application to “black” molybdenum prepared by CVD”, SPIE Proceedings Vol.401, 1983, p 330.Google Scholar
8. Handbook of Optical Constants of Solids, Palik, E. D., ed., Academic Press, Orlando, 1985.Google Scholar
9. Handbook of Chemistry and Physics, 74th Edition, Lide, D. R., Ed., CRC Press, Ann Arbor, 1994, pp 12–155 – 12–163.Google Scholar
10. Handbook of Tables for Applied Engineering Science, Ebolz, R. and Tuve, G. L., Ed, CRC Press, Cleveland, OH, 1973, pp 338–341.Google Scholar
11. Karlsson, B. and Ribbing, C. G., “Optical properties of transparent heat mirrors based on thin films of TiN, ZrN, and HfN”, SPIE Proceedings, Vol.324, 1982, p 52.Google Scholar
12. Handbook of Optics, Vol 2, Bass, M., ed., McGraw Hill, New York, 1995, p 25.8.Google Scholar