UN DISPOSITIVO DE HAZ ELECTRONICO

摘要

A device for recording or displaying images or for electron lithographic or electron microscopic uses, comprising in an evacuated envelope (1) a target (7) on which at least one electron beam (6) is focussed. This beam is generated by means of a semiconductor device (10) which comprises an electrically insulating layer (42) having an aperture (38) through which the beam passes. The layer carries at least four beam-forming electrodes (43 through 50) which are situated at regular intervals around the aperture (38). Each of the electrodes has such a potential that an n-pole field or a combination of n-pole fields is generated, where n is an even integer from 4 through 16. A suitable choice of the n-pole field will make it possible to impart substantially any desired shape to the beam (6) and thus the focus on the target.