FUNDAMENTAL OPTICAL-ABSORPTION EDGE OF SPUTTER-DEPOSITED ZIRCONIA AND YTTRIA

Zirconia and yttria films were sputter deposited onto unheated fused silica substrates using a metal target and rare gas‐oxygen discharges. Double‐beam spectrophotometry was used to measure the transmission and reflection as a function of incident photon energy, E, from which the absorption coefficient, α(E), was calculated. An indirect interband transition at Ei= 4.70 eV and two direct interband transitions at Eg1= 5.17 eV and Eg2= 5.93 eV occur in monoclinic zirconia. Two direct interband transitions at Eg1= 5.07 eV and Eg2= 5.73 eV occur in cubic yttria. The absorption edge structure is modified when unusual phases, such as tetragonal zirconia, and zirconia and yttria with no longrange crystallographic order, are present. Copyright © 1990, Wiley Blackwell. All rights reserved