Facile patterning of functional materials via gas-phase 3D printing
Authors:
Cesar Arturo Masse de la Huerta,
Viet H. Nguyen,
Abderrahime Sekkat,
Chiara Crivello,
Fidel Toldra-Reig,
Pedro Veiga,
Carmen Jimenez,
Serge Quessada,
David Muñoz-Rojas
Abstract:
Spatial Atomic Layer Deposition (SALD) is a recent approach that is up to two orders of magnitude faster than conventional ALD, and that can be performed at atmospheric pressure and even in the open air. Previous works have exploited these assets to focus on the possibility of high-rate, large-area deposition for scaling up into mass production. Conversely, here we show that SALD indeed represents…
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Spatial Atomic Layer Deposition (SALD) is a recent approach that is up to two orders of magnitude faster than conventional ALD, and that can be performed at atmospheric pressure and even in the open air. Previous works have exploited these assets to focus on the possibility of high-rate, large-area deposition for scaling up into mass production. Conversely, here we show that SALD indeed represents an ideal platform for the selective deposition of functional materials by proper design and miniaturization of SALD close-proximity heads. In particular, we have used the potential offered by 3D printing to fabricate custom close-proximity SALD injection heads. By using 3D printing, the heads can be easily designed and readily modified to obtain different deposition areas, free-form patterns, and even complex multimaterial structures. The heads can be printed in different materials to adjust to the chemistry of the precursors and the deposition conditions used. Polymeric heads can be used as cheap (even disposable) heads that are both used for performing deposition and for prototyping and optimization purposes. Finally, by designing a miniaturized head with circular concentric gas channels, 3D printing of functional materials can be performed with nanometric resolution in Z. This constitutes a new 3D printing approach based on gaseous precursors. Because the selective deposition strategies presented here are based on the SALD process, conformal and continuous thin films of functional materials can be printed at low temperatures and with high deposition rate in the open air. Our approach represents a new versatile way of printing functional materials and devices with spatial and topological control, thus extending the potential of SALD and ALD in general, and opening a new avenue in the field of area-selective deposition of functional materials.
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Submitted 9 June, 2020;
originally announced June 2020.
Neutron Beam Tests of $CsI(Na)$ and $CaF_{2}(Eu)$ Crystals for Dark Matter Direct Search
Authors:
Cong Guo,
Xinhua Ma,
Zhimin Wang,
Jie Bao,
Changjiang Dai,
Mengyun Guan,
Jinchang Liu,
Zuhao Li,
Jie Ren,
Xichao Ruan,
Changgen Yang,
Zeyuan Yu,
Weili Zhong,
Conett Huerta
Abstract:
In recent decades, inorganic crystals have been widely used in dark matter direct search experiments. To contribute to the understanding of the capabilities of $CsI(Na)$ and $CaF_{2}(Eu)$ crystals, a mono-energetic neutron beam is utilized to study the properties of nuclear recoils, which are expected to be similar to signals of dark matter direct detection. The quenching factor of nuclear recoils…
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In recent decades, inorganic crystals have been widely used in dark matter direct search experiments. To contribute to the understanding of the capabilities of $CsI(Na)$ and $CaF_{2}(Eu)$ crystals, a mono-energetic neutron beam is utilized to study the properties of nuclear recoils, which are expected to be similar to signals of dark matter direct detection. The quenching factor of nuclear recoils in $CsI(Na)$ and $CaF_{2}(Eu)$, as well as an improved discrimination factor between nuclear recoils and $γ$ backgrounds in $CsI(Na)$, are reported.
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Submitted 16 February, 2016;
originally announced February 2016.