SEM without black rectangles?

0481331 - ÚPT 2018 CZ eng A - Abstract
Frank, Luděk - Mikmeková, Eliška
SEM without black rectangles?
Mikroskopie 2017. Praha: Československá mikroskopická společnost, 2017. s. 20-21.
[Mikroskopie 2017. 09.05.2017-10.05.2017, Bratislava]
R&D Projects: GA TA ČR(CZ) TE01020118
EU Projects: European Commission(XE) 606988 - SIMDALEE2
Institutional support: RVO:68081731
Keywords : SEM * EBID of carbon * graphene
OECD category: Coating and films

Electron-beam-induced deposition (EBID) of various materials from suitable precursors represents an established branch of nanotechnology. A specific alternative is carbon deposition on the basis of hydrocarbons as precursors that has been applied to grow various nanostructures. Our area of study is unintentional EBID of carbon from spontaneously adsorbed hydrocarbon molecules. This process traditionally constitutes a challenge for SEM practice preventing one from performing any true surface studies outside an ultrahigh vacuum and without in-situ cleaning of samples. And even more, creation of black rectangles as traces of previous observation is obstructive when acquiring micrographs for presentations. However, we have shown that when reducing the energy of irradiating electrons sufficiently, the EBID can be converted to e-beam-induced release (or electron stimulated desorption, ESD) causing removal of hydrocarbons and ultimate cleaning of surfaces in both an ultrahigh and a standard high vacuum. Using series of experiments with graphene samples, we demonstrate fundamental features of the ESD and present results of checks for possible radiation damage using Raman spectroscopy that led to optimisation of the electron energy for damage-free cleaning. Removal of the amorphous carbon layer has also been evidenced by photoelectron spectroscopy and electron diffraction. The method of preventing carbon contamination described here paves the way for greatly enhanced surface sensitivity of imaging and substantially reduced demands on vacuum systems for nanotechnological applications. Moreover, it brings an efficient tool making easier the everyday job of microscopists.
Permanent Link: http://hdl.handle.net/11104/0276909