Effect of Plasma Cleaning on Carbon Support Films for Field Emission Gun

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Model 1020 Plasma Cleaner and Model 1070 NanoClean Effect of plasma cleaning on carbon support films for field emission gun transmission electron microscopy Analysis of specimens in a high-performance An oxygen-rich plasma will remove carbon field emission gun transmission electron from the film as the specimen is cleaned. If the microscopy (FEG TEM) requires removal of film is degraded excessively, the specimen may carbonaceous contamination in an instrument be lost. such as the Model 1020 Plasma Cleaner or the The standard operating parameters of both Model 1070 NanoClean. Fischione plasma cleaners can be modified NOTE to accommodate carbon support films. After To plasma clean cross section (XTEM) substituting 2% for the standard 25% oxygen specimens prepared with a focused ion beam (balance is argon), the gas pressure, gas flow, (FIB), it may be necessary to first place them on and RF power settings were optimized. The a support film such as carbon. This film is, in result was that the time for effective cleaning turn, supported by a standard metal grid often without film degradation was increased from formed from copper, nickel, or molybdenum. 20 seconds in 25% O2 to 2 minutes in 2% O2. PLASMA CLEANING CARBON SUPPORT FILMS A standard (~50 nm thick) carbon film supported by a 400-mesh copper grid is depicted after 2 minutes of plasma cleaning. TEM examination revealed no significant thinning of the film until it was plasma cleaned for times approaching 3 minutes. E.A. Fischione Instruments, Inc. 9003 Corporate Circle Export, PA 15632 USA Tel: +1 724.325.5444 Fax: +1 724.325.5443 [email protected] ©2014 E.A. Fischione Instruments, Inc. All rights reserved. www.fischione.com Document Number AN018 Revision 01 07/2014 APPLICATION.

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