Parylene anti-reflection coating of a quasi-optical hot-electron-bolometric mixer at terahertz frequencies

Citation
Hw. Hubers et al., Parylene anti-reflection coating of a quasi-optical hot-electron-bolometric mixer at terahertz frequencies, INFR PHYS T, 42(1), 2001, pp. 41-47
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
INFRARED PHYSICS & TECHNOLOGY
ISSN journal
1350-4495 → ACNP
Volume
42
Issue
1
Year of publication
2001
Pages
41 - 47
Database
ISI
SICI code
1350-4495(200102)42:1<41:PACOAQ>2.0.ZU;2-#
Abstract
Parylene C was investigated as anti-reflection coating for silicon at terah ertz frequencies. Measurements with a Fourier-transform spectrometer show t hat the transmittance of pure silicon can be improved by about 30% when app lying a layer of Parylene C with a quarter wavelength optical thickness. Th e 10% bandwidth of this coating extends from 1.5 to 3 THz for a center freq uency of 2.3-2.5 THz, where the transmittance is constant. Heterodyne measu rements demonstrate that the noise temperature of a hot-electron-bolometric mixer can be reduced significantly by coating the silicon lens of the hybr id antenna with a quarter wavelength Parylene C layer. Compared to the same mixer with an uncoated lens the improvement is about 30% at a frequency of 2.5 THz. (C) 2001 Elsevier Science B.V. All rights reserved.