Projection mask-less lithography and nanopatterning with electron and ion multi-beams

The projection charged particle multi-beam techniques of IMS Nanofabrication are based on illuminating a programmable Aperture Plate System (APS, consisting of an Aperture Plate and a Blanking Plate with integrated CMOS electronics) with a telecentric broad beam, to separate this beam into thousands of micrometer sized beams and to demagnify the beamlets thus formed to nanometer dimensions, using projection charged particle optics with 200x reduction. Only beams which are unaffected by the Blanking Plate are projected to the substrate whereas beams which are slightly tilted are filtered out at a contrast aperture. Both, electron and ion multi-beam, proof-of-concept test systems were realized based on this concept. With a 43k- APS, which provides up to 43-thousand programmable 12.5nm sized beams, complex patterns were realized in 20 μm × 20 μm exposure fields using 10 keV H3+ ions. For the electron multibeam test system the beam diameter at the APS was limited to 2 mm, thus realizing 2500 programmable electron beams of 12.5nm size and 50 keV energy. Application fields of projection electron and ion multi-beam projection techniques are discussed.