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Results for “Plasma processing”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Plasma Processing of SRF Cavities for the Next Generation of Particle Accelerators

What are the major goals of the project? Goal 1: Optimize interactively processing of the single-cell cavity by combining plasma treatment and vertical cold bath testing. Continue using single cell cavity as the test bed for new applications. Goal 2: Work on upgrading the plasma etching technology for multi-cell SRF cavities. Goal 3: Develop and adapt discharge configurations to critical cavity regions including the electron beam weld (EBW) and iris areas. Goal 4: Develop tailored methods to prepare surface properties for a specific function prior to any additional modification, such as (but not limited to) surface passivation in preparation of other superconducting materials and structures.

43 PARTICLE ACCELERATORS↗
DOE OSTI2019

Lithographically patterned metallic conduction in single-layer MoS2 via plasma processing

Tailoring the electrical transport properties of two-dimensional transition metal dichalcogenides can enable the formation of atomically thin circuits. In this work, cyclic hydrogen and oxygen plasma exposures are utilized to introduce defects and oxidize MoS 2 in a controlled manner. This results in the formation of sub-stochiometric MoO 3-x , which transforms the semiconducting behavior to metallic conduction. To demonstrate functionality, single flakes of MoS 2 were lithographically oxidized using electron beam lithography and subsequent plasma exposures. This enabled the formation of atomically thin inverters from a single flake of MoS 2 , which represents an advancement toward atomically thin circuitry.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Large-Scale Synthesis of Colloidal Si Nanocrystals and Their Helium Plasma Processing into Spin-On, Carbon-Free Nanocrystalline Si Films

This study describes a simple approach to the large-scale synthesis of colloidal Si nanocrystals and their processing into spin-on carbon-free nanocrystalline Si films. The synthesized silicon nanoparticles are capped with decene, dispersed in hexane, and deposited on silicon substrates. The deposited films are exposed to nonoxidizing room-temperature He plasma to remove the organic ligands without adversely affecting the silicon nanoparticles to form crack-free thin films. We further show that the reactive ion etching rate in these films is 1.87 times faster than that for single-crystalline Si, consistent with a simple geometric argument that accounts for the nanoscale roughness caused by the nanoparticle shape.

36 MATERIALS SCIENCE↗