Translator Disclaimer
11 September 1989 Infrared Properties (3-5 μm) Of Ion Plated Thin Films
Author Affiliations +
Thin films deposited by standard electron beam evaporation have a columnar microstructure and consequential water adsorption which is not prevalent in fully dense ion plated optical coatings. In electron beam evaporated films the water becomes an intrinsic part of the film since the packing density is less than unity, and causes absorption at and around 3 μm. In contrast, the absence of water in ion plated films makes a number of oxide coatings suitable for use in the first atmospheric window (3-5 μm). In this study, the spectral transmission curves of single layer and broadband multilayer coatings in the 4000 - 2000 cm-1 range show clearly that ion plated coatings do not contain any water, while electron beam evaporated thin films have strong absorption around 3400 cm-1. The refractive indices of several oxide, silicon nitride, and pure silicon films are shown to be consistently higher for ion plating than for electron beam evaporation, also indicating a higher packing density.
© (1989) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
K. H. Guenther, P. Sachdeva, and Z. Taubenfeld "Infrared Properties (3-5 μm) Of Ion Plated Thin Films", Proc. SPIE 1112, Window and Dome Technologies and Materials, (11 September 1989);

Back to Top