Design of a high brightness multi-electron-beam source

An electron optics design is presented for forming 100 high brightness beamlets from a single "Schottky" type "thermal field emission" source, such as used in present day electron microscopes and lithography machines. The footprint of the whole system is only 1.5x1.5 mm, so that it can be used as one element in an array of many elements for application in high throughput maskless lithography or high throughput electron beam inspection. Novel electron optical components are used such as an array of electrostatic aperture lenses with an 85% filling factor and a zero-strength electrostatic decelerating lens. For a source brightness of 10(8) A/m(2)srV, each beamlet can deliver 15 nA without an increase of the spot diameter by lens aberrations. (C) 2008 Elsevier B. V. All rights reserved.