A method of generating a layout pattern includes determining a first energy density indirectly exposed to a first feature of one or more features of a layout pattern on an energy-sensitive material when the one or more features of the layout pattern on the energy-sensitive material are directly exposed by a charged particle beam. The method also includes adjusting a second energy density exposed the first feature when the first feature is directly exposed by the charged particle beam. A total energy density of the first feature that comprises a sum of the first energy density from the indirect exposure and the second energy density from the direct exposure is maintained at about a threshold energy level to fully expose the first feature in the energy-sensitive material.

In one embodiment, a charged particle beam writing method includes virtually dividing a writing region of the substrate into a plurality of first mesh regions in a first mesh size, calculating an area density of the pattern for each of the plurality of first mesh regions to generate first mesh data, converting a mesh size of the first mesh data into a second mesh size greater than the first mesh size to generate second mesh data, performing a convolution operation between the second mesh data and a proximity effect correction kernel to generate third mesh data, converting a mesh size of the third mesh data into the first mesh size to generate fourth mesh data, performing a convolution operation between the first mesh data and a middle range effect correction kernel to generate fifth mesh data, and adding the fourth mesh data and the fifth mesh data together to calculate an irradiation amount of the charged particle beam for each of the plurality of first mesh regions.

A beam irradiation device that irradiates a plurality of electron beams includes a multibeam optical system that emits the plurality of beams to be irradiated on a target; and a controller that controls an irradiation state of each of the plurality of beams in accordance with change in a relative position between the target and the multibeam optical system, and based on the irradiation state of a first beam of the plurality of beams, controls the irradiation state of a second beam of the plurality of beams.

Disclosed is a lithography process on a sample including at least one structure and covered by at least a lower layer of resist and a upper layer of resist the process including: using an optical device to image or determine, in reference to the optical device, a position of the selected structure and positions of markers integral with the sample; using an electron-beam device, imaging or determining the position of each marker in reference to the electron-beam device; deducing the position of the selected structure in reference to the electron-beam device; exposing to an electron beam the upper layer of resist above the position of the selected structure to remove all the thickness of the upper layer of resist above the position of the selected structure but none or only part of the thickness of the lower layer of resist above the position of the selected structure.

Methods include inputting an array of pixels, where each pixel in the array of pixels has a pixel dose. The array of pixels represents dosage on a surface to be exposed with a plurality of patterns, each pattern of the plurality of patterns having an edge. A target bias is input. An edge of a pattern in the plurality of patterns is identified. For each pixel which is in a neighborhood of the identified edge, a calculated pixel dose is calculated such that the identified edge is relocated by the target bias. The array of pixels with the calculated pixel doses is output. Systems for performing the methods are also disclosed.

Position shifts caused by charging phenomena can be corrected with high accuracy. A charged particle beam writing apparatus includes an exposure-amount distribution calculator calculating an exposure amount distribution of a charged particle beam using a pattern density distribution and a dose distribution, a fogging charged particle amount distribution calculator calculating a plurality of fogging charged particle amount distributions by convoluting each of a plurality of distribution functions for fogging charged particles with the exposure amount distribution, a charge-amount distribution calculator calculating a charge amount distribution due to direct charge using the pattern density distribution, the dose distribution, and the exposure amount distribution, and calculating a plurality of charge amount distributions due to fogging charge using the plurality of fogging charged particle amount distributions, a position shift amount calculator calculating a position shift amount of a writing position based on the charge amount distribution due to direct charge and the plurality of charge amount distributions due to fogging charge, a corrector correcting an exposure position using the position shift amount, and a writer exposing the corrected exposure position to a charged particle beam.

A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.

In one embodiment, a writing data generation method is for generating writing data used by a multi-charged particle beam writing apparatus. The writing data generation method includes referring to library data in which a vertex sequence including a plurality of vertices is registered, and extracting a portion of an outer line of a figure contained in design data, the portion corresponding to the vertex sequence, and representing the extracted portion by information which identifies the vertex sequence and information which indicates a connection method for the plurality of vertices of the vertex sequence, and generating the writing data.

A method for projecting a particle beam onto a substrate, the method includes a step of calculating a correction of the scattering effects of the beam by means of a point spread function modelling the forward scattering effects of the particles; a step of modifying a dose profile of the beam, implementing the correction thus calculated; and a step of projecting the beam, the dose profile of which has been modified, onto the substrate, and being wherein the point spread function is, or comprises by way of expression of a linear combination, a two-dimensional double sigmoid function. A method to e-beam lithography is also provided.

An electron beam irradiation method includes calculating a charge amount distribution in the case where a substrate is irradiated with an electron beam, by using an index indicating complexity of a pattern to be formed on the substrate, calculating a positional deviation amount of an irradiation pattern to be formed due to irradiation with the electron beam, by using the charge amount distribution having been calculated, correcting an irradiation position by using the positional deviation amount having been calculated, and applying an electron beam to the irradiation position having been corrected.