Characterization and application of cerium fluoride film in infrared antireflection coating

• Published in: Infrared physics & technology Vol. 52; no. 5; pp. 204 - 207
• Main Authors: Su, Wei-tao, Li, Bin, Liu, Ding-quan, Zhang, Feng-shan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2009; Elsevier
• Subjects: Broadband antireflection coating; CeF 3 thin film; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Fundamental areas of phenomenology (including applications); General theory; Infrared optical properties; Morphology; Optical coatings; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical elements, devices, and systems; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Optics; Physics; 78.30.Hv; Broadband antireflection coating; CeF 3 thin film; Infrared optical properties; Morphology; 78.20.Ci; 78.20.Bh; Scanning electron microscopy; Fourier transformation; CeF; Cerium fluoride; XRD; Electron microscopy; Thin films; Optical properties; Germanium; thin film; Optical coatings; Optical constants; Antireflection coatings
• ISSN: 1350-4495; 1879-0275
• DOI: 10.1016/j.infrared.2009.07.008

Cerium fluoride (CeF 3) thin films were evaporated to the germanium substrates at different substrate temperature from 100 °C to 250 °C. Structural and optical properties were characterized by X-ray diffraction (XRD), scan electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The morphology of samples deposited at different temperature can be closely related to preferred orientation. The infrared optical constants were obtained by fitting the transmission spectrum using Lorentz oscillator model. A simple example for fabrication of long-wave infrared broadband antireflection coating was also presented.