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Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping.

ABSTRACT: Background: Electron-beam shaping opens up the possibility for novel imaging techniques in scanning (transmission) electron microscopy (S(T)EM). Phase-modulating thin-film devices (phase masks) made of amorphous silicon nitride are commonly used to generate a wide range of different beam shapes. An additional conductive layer on such a device is required to avoid charging under electron-beam irradiation, which induces unwanted scattering events. Results: Phase masks of conductive amorphous carbon (aC) were successfully fabricated with optical lithography and focused ion beam milling. Analysis by TEM shows the successful generation of Bessel and vortex beams. No charging or degradation of the aC phase masks was observed. Conclusion: Amorphous carbon can be used as an alternative to silicon nitride for phase masks at the expense of a more complex fabrication process. The quality of arbitrary beam shapes could benefit from the application of phase masks made of amorphous C.

SUBMITTER: Grunewald L

PROVIDER: S-EPMC6604735 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping.

Grünewald Lukas L Gerthsen Dagmar D Hettler Simon S

Beilstein journal of nanotechnology 20190625

<b>Background:</b> Electron-beam shaping opens up the possibility for novel imaging techniques in scanning (transmission) electron microscopy (S(T)EM). Phase-modulating thin-film devices (phase masks) made of amorphous silicon nitride are commonly used to generate a wide range of different beam shapes. An additional conductive layer on such a device is required to avoid charging under electron-beam irradiation, which induces unwanted scattering events. <b>Results:</b> Phase masks of conductive a ...[more]

PMID: 31293866

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