• search hit 19 of 22
Back to Result List

Environmentally stable iridium mirror coatings for the infrared spectral range

  • Highly reflective metal coatings are essential for numerous optical elements. Established mirror coatings made of silver (Ag) and gold (Au) offer high and broadband self-reflection in the infrared (IR) spectral range but are susceptible to environmental influences and mechanical stress without suitable protective layers. In the long-wavelength spectral range, in particular, the absorption bands of these protective layers partially reduce the high mirror reflectivity again. However, the noble metal iridium (Ir) is hard, extremely dense, and thermally, mechanically, and chemically stable. Iridium provides a similarly high reflectivity in the mid (MIR) and far-infrared (FIR) spectral range, as silver and gold, and high resistance to environmental influences - even without protective layers. In this paper, the different deposition processes, as well as the optical and structural properties of iridium mirror coatings fabricated by atomic layer deposition (ALD) and by magnetron sputtering (MS), are presented and compared with each other. The complex refractive indices for ALD and MS deposited iridium mirror coatings were determined for wavelengths from 200 nm to 20 μm, complementing the existing literature values. We demonstrate that iridium mirror coatings offer a high and broadband reflectivity from the mid to far-infrared spectral range. In contrast to established – protected – silver and gold mirror coatings, the iridium coatings are environmentally durable and thermally stable up to 600 °C, even without protective layers. Therefore, as an interesting mirror coating material, iridium has the potential for special applications in infrared astronomy and probably also for industrial instruments.
Metadaten
Author:Thorsten DöhringORCiD, Manfred StollenwerkORCiD, Paul Schmitt, Adriana Szeghalmi
DOI:https://doi.org/https://doi.org/10.1117/12.2632057
Parent Title (English):Proceedings of SPIE
Publisher:SPIE
Document Type:Conference Proceeding
Language:English
Year of Completion:2022
Date of first Publication:2022/07/15
Creating Corporation:TH Aschaffenburg
Contributing Corporation:Fraunhofer-Institut IOF Jena
Release Date:2022/07/26
Tag:atamic layer deposition; coating; iridium; magnetron sputtering; reflectivity
GND Keyword:Iridium; Beschichtung
Volume:2022
Issue:12298
Page Number:8
First Page:122980A-1
Last Page:122980A-08
Urheberrecht:1
Institutes:Fakultät Ingenieurwissenschaften / Studiengänge / Internationales Technisches Vertriebsmanagement (Bachelor)
research focus :Materials / Innovative Material Processing
Licence (German):Keine Lizenz - es gilt das deutsche Urheberrecht
Einverstanden ✔
Diese Webseite verwendet technisch erforderliche Session-Cookies. Durch die weitere Nutzung der Webseite stimmen Sie diesem zu. Unsere Datenschutzerklärung finden Sie hier.