GB1321172A - Method and device for obtaining parallel and focused ionic microbeams and application of said method to the collective formation of electric circuits by ion implantation - Google Patents

Abstract

1321172 Mass separators; ion implantation into semi-conductors COMMISSARIAT A L'ENERGIE ATOMIQUE 19 Jan 1971 [20 Jan 1970] 2519/71 Headings H1D and H1K A method of obtaining identical parallel focused beams of monoenergetic ion beams of a single isotope suitable for simulataneous production of identical circuits by ion implantation comprises three stages 1, 6 and 11: a beam of monoenergetic ions of a single isotope leave stage 1; the input beam to stage 6 is transformed to a broad cross-section parallel beam which is then split into parallel focused microbeams which leave stage 6; the microbeams are focused on to the sample 13, e.g. a semiconductor material which is provided in stage 11. The beam 3 from an ion source, e.g. of the duoplasmatron type is focused by a system 4 of quadruple lenses producing a convergent beam of about 30 KeV. which passes through a double-focusing electro-magnet isotope separator 5. A system 8 of quadruple lenses produces a broad parallel beam which passes through tube 9 comprising coaxial frustoconical rings and producing a substantially uniform electric field which is adjustable so as to vary the depth of ionic penetration in sample 13. The device 10 comprises a system of quadruple microlenses having filiform electrodes and producing microbeams focused on the sample 13 which is displaceable relative to the beams preferably by a computer control 14. The ion dopants may be Li, B, Al, P, Ga, As, Cu, Zn, In and Au and the microbeams have a diameter of 1 micron and an energy between about 10 KeV and 180 KeV.