Application and Development of Atomic Layer Deposition Techniques to Improve Thermo-optical Coatings for Spacecraft Thermal Control and Advanced Optical Instruments

Date

2019-07-07

Journal Title

Journal ISSN

Volume Title

Publisher

49th International Conference on Environmental Systems

Abstract

A key technology development driver in environmental control systems and next generation optics are discussed utilizing thin film development borrowed from the semiconductor industry. The optical and physical properties of spacecraft radiator coatings are dictated by orbital environmental conditions. For example, coatings must adequately dissipate charge buildup when orbital conditions, such as polar, geostationary or gravity neutral, result in surface charging. Current dissipation techniques include depositing a layer of ITO (indium tin oxide) on the radiator surface in a high temperature process. The application of these enhanced coatings must be such that the properties in question are tailored to mission-specific requirements. The multi-billion-dollar semiconductor industry has adopted Atomic Layer Deposition (ALD) for self-assembly and atomic-scale placement. ALD is a cost-effective nanoadditive-manufacturing technique that allows for the conformal coating of substrates with atomic control in a benign temperature and pressure environment. By using ALD, modification of these coatings can be accomplished during coating application preprocessing. The preprocessing is rendered directly on the coating dry pigment before binding. Through the introduction of paired precursor gases, thin films can be deposited on a myriad of substrates ranging from glass, polymers, aerogels, metals, powders, and other high aspect-ratio micro- and nano-structures. By providing atomic-level control, where single layers of atoms can be deposited, the fabrication of metal transparent films, precise nano-laminates, and coatings of nano-channels and pores is achievable. A method has been demonstrated for the ALD of In2O3 and films on a variety of substrates from Si(100) wafers, glass slides, and on Z93P pigments resulting in a direct spaceflight application. Results will be presented that verify the chemical composition of ALD pigments and charge dissipation properties when the pigment goes through its binding and coating process and we present early results of ALD for carbon nanotube formation.

Description

Vivek Dwivedi, National Aeronautics and Space Administration (NASA), USA
Mark Hasegawa, National Aeronautics and Space Administration (NASA), USA
Raymond Adomaitis, University of Maryland, USA
Hossein Salami, University of Maryland, USA
Alan Uy, University of Maryland, USA
Corinne Grob, University of Maryland, USA
Aarathi Vadapalli, University of Maryland, USA
ICES104: Advances in Thermal Control Technology
The 49th International Conference on Environmental Systems as held in Boston, Massachusetts, USA on 07 July 2019 through 11 July 2019.

Keywords

Atomic Layer Deposition, Thin Films, Radiator, Indium Oxide, Copper, Semiconductor, Pigments, Carbon Nanotubes

Citation