Abstract: A particle beam generator comprising particle extraction means disposed adjacent a particle source and operable to extract particles from such a source into an extraction aperture of the extraction means to form a particle beam, particle accelerating means operable to accelerate the extracted particles to increase the energy of the beam, and focussing means operable to focus the particle beam, each of said extraction means, accelerating means and focussing means being arranged in sequence and having apertures therethrough and in alignment to define a passageway through which the particles are constrained to move, characterised in that the extraction means comprises a lens structure comprising at least a pair of electrodes separated by a layer of insulating material allowing the application of different potentials to each of the lens structure electrodes, one of said electrodes comprising an extraction plate having an extraction aperture formed therein, by means of which extraction plate particles may be drawn

Abstract: A mask suitable for use with a particle beam source such as ion or electron source for forming features and structures and writing on surfaces of materials. The mask comprising an aperture plate, having a plurality of apertures, and focusing means disposed to underlie the aperture plate. The plurality of apertures forming an array whereby each plate aperture is adapted to receive a portion of a particle beam incident on the aperture plate. Each portion of particle beam then passes through focusing means through which the portion of beam is focused onto the surface. The mask thereby forming a plurality of high resolution simultaneously operable focused particle beams.

Abstract: An accelerating tube for an electrostatic particle accelerator is composed of a plurality of rings of insulating material interleaved with annular metal discs. The discs are interconnected externally of the tube by resistor bridges in a manner to provide a decoupled zone somewhere along the potential gradient and within this zone particle trapping electrodes are placed to take out low energy particles near the periphery of the main beam with reduced secondary particle generation.