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A TIP OSCILLATION PHENOMENON

November 1987
Le Journal de Physique Colloques 48(C6)

DOI:10.1051/jphyscol:1987635

Authors:

Une étude des cous stables des pointes en microscopie électronique transmission montre l'existence d'une oscillation des pointes avec des amplitudes de ~ 200 Å et des fréquences de ~ 0.3 Hertz (Cu, Au, 900°C). L'oscillation est expliquée par une interaction de deux forces : (1) une force électro-statique causée par l'impact des électrons et annihilée par une décharge d'émission de champ et (2) une force élastique d'une couche graphitique à la surface de la pointe. A detailed study of stable tip necks by in situ transmission electron microscopy shows an existence of tip oscillations with amplitudes in the order of 200 Å and frequencies in the order of 0.3 Hertz (Cu, Au at ~ 900°C). The oscillation is explained by an interaction of two forces : (1) an electrostatic force caused by electron impact and annihilated by a field emission discharge and (2) an elastic force of a graphitized layer on the tip surface.

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Last Updated: 22 Oct 2024