Fourier microstructuring

摘要

Previous methods for microstructuring expose the photoresist either by means of a punctiform electron probe and are limited in terms of resolution by the probe size or illuminate the sample globally and are limited in terms of resolution by the lens aberrations. The arrangement presented serves to produce microscopic structures. For this purpose, electrons are accelerated from a field emission source (1) in the z direction, guided onto a first electron biprism (3) whose filament is in the y direction, and subsequently guided onto a second electron biprism (4) whose filament is in the x direction. The electrons then interfere on the electron-beam sensitive photoresist (9). The electron beam current (6) is modulated by a computer. During the write operation, the filament voltage (11) (12) is changed on both biprisms, the entire two-dimensional Fourier space being imaged in the form of the different interference patterns on the photoresist. The Fourier-transformed image, which is present in the computer (13), of the structure to be written supplies the information for the modulation of the electron beam current. The Fourier microstructuring method is used in all areas of microstructuring in which structures are to be produced right into the atomic range.