A direct imaging system includes an optical modulator having multiple elements arranged corresponding to a sub scanning direction and for modulating light from a light source, and an exposure head for exposing the substrate with the light modulated by the optical modulator. A control part relatively moves the exposure head in a main scanning direction to expose the sub exposure area with the light modulated using a selection element, and after the sub exposure area is exposed, relatively moves the exposure head an amount corresponding to a sub exposure width in the sub scanning direction. Accordingly, exposure can be continued even if there is a defect in the optical modulator.

A method for patterning a substrate involves depositing a layer of resist material on a surface of the substrate, lithographically patterning (electron beam exposing and then developing) the layer of the resist material to form a patterned resist layer having a pattern multi-faceted microscale structures with a depth profile that varies over an area of the layer of resist material, and using the patterned resist layer in an etching step to transfer the pattern of multi-faceted microscale structures from the patterned resist layer to the substrate.

In one embodiment, an aperture correction amount calculation method is for calculating a correction amount for positions or dimensions of a plurality of apertures formed in an aperture array substrate through which multiple charged particle beams pass. The method includes measuring a shift amount distribution on an irradiation surface, which is a distribution of shift amounts from a predetermined position or a predetermined current density of each beam within a beam array of the multiple charged particle beams, dividing the beam array into a predetermined number of block regions based on the shift amount distribution, and calculating a representative value of the shift amounts corresponding to each block region, and calculating, for each of the block regions, correction amounts for positions or dimensions of the corresponding apertures of the aperture array substrate based on the representative values.

A system includes a memory and at least one processing device, operatively coupled to the memory, to generate a square pixel pattern for rasterizing an image, rasterize the image using the square pixel pattern to generate a raster image, wherein the raster image is stored in a file usable by a digital lithography system, and cause the digital lithography system to pattern a substrate based on the raster image having the square pixel pattern.

In one embodiment, a multibeam writing method includes acquiring a current density distribution of multiple beams formed using a charged particle beam emitted from a charged particle source, comparing the acquired current density distribution with a preset ideal shape of the current density distribution, and performing a beam adjustment on the multiple beams in a case where a difference at a predetermined position is greater than a threshold value.