Influence of deposition parameters on the optical absorption of amorphous silicon thin films

Terkowski, L. et al. (2020) Influence of deposition parameters on the optical absorption of amorphous silicon thin films. Physical Review Research, 2(3), 033309. (doi: 10.1103/PhysRevResearch.2.033308)

Abstract

Amorphous silicon (aSi) is a promising material for application in mirror coatings with low thermal noise in future gravitational-wave detectors. However, the optical absorption of aSi is currently too high to meet the requirements of these instruments. Previously measured absorption values vary significantly for different deposition methods and postdeposition treatments. To investigate the absorption of aSi, we systematically varied key deposition parameters using pulsed laser deposition. Varying the deposition temperature resulted in a spread in mobility gap energy of the aSi; however, no clear correlation of temperature and mobility gap could be observed. Varying the pulse energy and repetition frequency altered the deposition rate of the coating and produced a correlated change in the absorption.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Rowan, Professor Sheila and Bassiri, Mr Riccardo and Bell, Dr Angus and Martin, Dr Iain and Steinlechner, Dr Jessica and Hough, Professor James
• Authors: Terkowski, L., Martin, I. W., Axmann, D., Behrendsen, M., Pein, F., Bell, A., Schnabel, R., Bassiri, R., Fejer, M. M., Hough, J., Markosyan, A., Rowan, S., and Steinlechner, J.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Research Centre: College of Science and Engineering > School of Physics and Astronomy > Institute for Gravitational Research
• Journal Name: Physical Review Research
• Publisher: American Physical Society
• ISSN: 2643-1564
• ISSN (Online): 2643-1564
• Published Online: 26 August 2020
• Copyright Holders: Copyright © 2021 American Physical Society
• First Published: First published in Physical Review Research 2(3): 033309
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
173808		Investigations in gravitational radiation	Sheila Rowan	Science and Technology Facilities Council (STFC)	ST/N005422/1	P&S - Physics & Astronomy
166497		Optical characterisation of silicon and mirror materials for gravitational astronomy.	Iain Martin	The Royal Society (ROYSOC)	RG110331	P&S - Physics & Astronomy