METHOD FOR ESTIMATING PATTERNS TO BE PRINTED ON A PLATE OR MASK BY MEANS OF ELECTRON-BEAM LITHOGRAPHY AND CORRESPONDING PRINTING DEVICE

摘要

This method for estimating patterns (M′PF,D′PF) to be printed by means of electron-beam lithography, comprises the following steps: printing (100), in a resin, a set of calibration patterns (MCF, DCF); measuring (120) characteristic dimensions (CD) of this set; supplying an estimation (140) of the point spread function (PSF) based on the characteristic dimensions (CD) measured; estimating (160) the patterns (M′PF,D′PF) to be printed by convoluting the point spread function (PSF) supplied with an initial value of the patterns (MPF,DPF).;Furthermore, each calibration pattern printed includes a central zone exposed to the electron beam and a plurality of surrounding concentric zones with rotational symmetry. The characteristic dimensions measured are characteristic dimensions (CD) of the central zones of the patterns. The estimation of the point spread function (PSF) is calculated by inverting analytical modelling of the effect, on these characteristic dimensions, of applying the first point spread function portion (PSFBE) characterising electrons back-scattered by the substrate to the set of calibration patterns (MCF, DCF).

主权项

1. A method for estimating patterns to be printed on a plate or mask by electron-beam lithography, comprising the following steps:
printing with electron-beam lithography, in a resin arranged on a substrate, a set of calibration patterns, measuring characteristic dimensions of the set of calibration patterns after printing, and saving said characteristic dimensions to memory, supplying, with a processor having access to the memory, an estimation of the point spread function characterising electrons scattered during printing, based on the characteristic dimensions measured, estimating the patterns to be printed by convoluting the point spread function supplied with an initial value of said patterns to be printed,wherein:
each calibration pattern printed in the resin includes a central zone exposed to the electron beam and a plurality of concentric zones with rotational symmetry arranged about this central zone, the characteristic dimensions measured after printing are characteristic dimensions of the central zones of the patterns, and estimating the point spread function is calculated as the sum of a first point spread function portion characterising electrons back-scattered by the substrate and a second point spread function portion characterising electrons scattered in the resin, and comprises an inversion of analytical modelling of the effect, on said characteristic dimensions, of applying the first point spread function portion to the set of calibration patterns.