Patent ID: 9269543
Filing Date: 2016-02-23
CPC Classification: H01J

Claim Text:
1. Method for computing an exposure pattern for exposing a desired pattern on a target by means of a blanking aperture array in a particle-optical lithography apparatus taking into account a finite number of defects in said blanking aperture array, said desired pattern being composed of a multitude of image elements within an image area on the target, wherein the blanking aperture array comprises a plurality of blanking apertures arranged within a blanking array area in a predetermined arrangement defining mutual positions of the blanking apertures, each blanking aperture being selectively adjustable with regard to a dose value to be exposed through the respective blanking aperture onto a corresponding aperture image on the target during a respective exposure interval, said dose value taking a value within a common dose interval between a minimum value and a maximum value, with the exception of a finite number of defective blanking apertures, each defective blanking aperture exposing either a respective constant dose value or a dose interval incompatible with the common dose interval onto a corresponding aperture image on the target during an exposure interval, wherein during a writing process, a sequence of exposure intervals is made, wherein in each exposure interval the blanking apertures are imaged onto the target, thus generating a corresponding plurality of aperture images, wherein the position of aperture images is kept fixed relative to the target during an exposure interval and coincides with the position of an image element, but between exposure intervals the position of aperture images is shifted over the target, thus exposing a plurality of aperture images so as to cover all image elements within said image area on the target, wherein the method comprises: