Optical constants of crystalline WO₃ deposited by magnetron sputtering

Authors

Michael J. DeVries, University of Nebraska-Lincoln
Chris Trimble, University of Nebraska-Lincoln
Thomas E. Tiwald, University of Nebraska-Lincoln
Daniel W. Thompson, University of Nebraska-LincolnFollow
John A. Woollam, University of Nebraska-LincolnFollow
Jeffrey S. Hale, J. A. Woollam Co., Lincoln, Nebraska

Document Type

Article

Date of this Version

9-1-1999

Comments

Published in J. Vac. Sci. Technol. A 17„(5), Sep/Oct 1999. ©1999 American Vacuum Society. Used by permission.

Abstract

Crystalline WO_3-x is an infrared (IR) electrochromic material having possible applications in satellite thermal control and IR switches. Optical constants of electrochromic materials change upon ion intercalation, usually with H⁺ or Li⁺. Of primary concern for device design are the optical constants in both the intercalated and deintercalated states. In situ and ex situ ellipsometric data are used to characterize both the deposition process and the optical constants of the films. Ex situ data from a UV-Vis-NIR ellipsometer are combined with data from a mid-infrared Fourier-transform-infrared-based ellipsometer to provide optical constants over a spectral range of 0.031–6.1 eV.