The Open UniversitySkip to content
 

Modelling electron distributions within ESA's Gaia satellite CCD pixels to mitigate radiation damage

Seabroke, G. M.; Holland, A. D.; Burt, D. and Robbins, M. S. (2009). Modelling electron distributions within ESA's Gaia satellite CCD pixels to mitigate radiation damage. In: SPIE Conference on Astronomical and Space Optical Systems, 2-5 August 2009, San Diego, CA, USA, p. 743905.

Full text available as:
[img]
Preview
PDF (Accepted Manuscript) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (2682Kb)
DOI (Digital Object Identifier) Link: http://dx.doi.org/10.1117/12.825693
Google Scholar: Look up in Google Scholar

Abstract

The Gaia satellite is a high-precision astrometry, photometry and spectroscopic ESA cornerstone mission, currently scheduled for launch in 2012. Its primary science drivers are the composition, formation and evolution of the Galaxy. Gaia will achieve its unprecedented positional accuracy requirements with detailed calibration and correction for radiation damage. At L2, protons cause displacement damage in the silicon of CCDs. The resulting traps capture and emit electrons from passing charge packets in the CCD pixel, distorting the image PSF and biasing its centroid. Microscopic models of Gaia's CCDs are being developed to simulate this effect. The key to calculating the probability of an electron being captured by a trap is the 3D electron density within each CCD pixel. However, this has not been physically modelled for the Gaia CCD pixels. In Seabroke, Holland & Cropper (2008), the first paper of this series, we motivated the need for such specialised 3D device modelling and outlined how its future results will fit into Gaia's overall radiation calibration strategy. In this paper, the second of the series, we present our first results using Silvaco's physics-based, engineering software: the ATLAS device simulation framework. Inputting a doping profile, pixel geometry and materials into ATLAS and comparing the results to other simulations reveals that ATLAS has a free parameter, fixed oxide charge, that needs to be calibrated. ATLAS is successfully benchmarked against other simulations and measurements of a test device, identifying how to use it to model Gaia pixels and highlighting the affect of different doping approximations.

Item Type: Conference Item
Copyright Holders: 2009 The Authors
Academic Unit/Department: ?? scie-pssr ??
Science > Physical Sciences
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 19176
Depositing User: George Seabroke
Date Deposited: 09 Dec 2009 09:46
Last Modified: 24 Oct 2012 11:26
URI: http://oro.open.ac.uk/id/eprint/19176
Share this page:

Altmetrics

Scopus Citations

Actions (login may be required)

View Item
Report issue / request change

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340   general-enquiries@open.ac.uk