Patent classifications
H01J2237/31776
Method of pattern data preparation and method of forming pattern in layer
A method of pattern data preparation includes the following steps. A desired pattern to be formed on a surface of a layer is inputted. A first set of beam shots are determined, and a first calculated pattern on the surface is calculated from the first set of beam shots. The first calculated pattern is rotated, so that a boundary of the desired pattern corresponding to a non-smooth boundary of the first calculated pattern is parallel to a boundary constituted by beam shots. A second set of beam shots are determined to revise the non-smooth boundary of the first calculated pattern, thereby calculating a second calculated pattern being close to the desired pattern on the surface. The present invention also provides a method of forming a pattern in a layer.
METHOD AND SYSTEM FOR DETERMINING A CHARGED PARTICLE BEAM EXPOSURE FOR A LOCAL PATTERN DENSITY
A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.
CHARGED PARTICLE BEAM WRITING METHOD AND CHARGED PARTICLE BEAM WRITING APPARATUS
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.
CHARGED PARTICLE BEAM WRITING METHOD AND CHARGED PARTICLE BEAM WRITING APPARATUS
In one embodiment, a charged particle beam writing method includes dividing a figure pattern defined in writing data into a plurality of shot figures, virtually dividing a writing target substrate into a plurality of mesh regions, and calculating a correction irradiation amount to correct proximity effect and middle range effect for each of the mesh regions based on a position of the figure pattern, calculating an irradiation amount for each of the plurality of shot figures using the correction irradiation amount, calculating an insufficient irradiation amount at an edge portion of the shot figure based on the irradiation amount, resizing the shot figure based on the insufficient irradiation amount, and writing the resized shot figure on the writing target substrate using a charged particle beam in the irradiation amount.
Adapting the Duration of Exposure Slots in Multi-Beam Writers
In a charged-particle lithography apparatus, during writing a desired pattern, the duration of exposure slots is adapted to compensate for fluctuations of the particle beam. In the writing process the aperture images are mutually overlapping on the target so each pixel is exposed through a number of aperture images overlapping at the respective pixel, which results in an exposure of the respective pixel through an effective pixel exposure time, i.e., the sum of durations of contributing exposure slots, and the exposure slot durations are adjusted by: (i) determining a desired duration of the effective pixel exposure time for the pixels, as a function of the time of exposure of the pixels, (ii) determining contributing exposure slots for the pixels, (iii) calculating durations for the contributing exposure slots thus determined such that the sum of the durations over said contributing exposure slots is an actual effective exposure time which approximates said desired duration of the effective pixel exposure time.
The durations in step (iii) are calculated in accordance with a predetermined set of allowed durations, wherein at least one of the durations thus calculated is different from the other durations selected for said set of exposure slots
MULTI CHARGED PARTICLE BEAM WRITING APPARATUS AND MULTI CHARGED PARTICLE BEAM WRITING METHOD
In one embodiment, a multi charged particle beam writing apparatus includes a measurement unit measuring a first beam shape of a multi-beam based on a beam current of each beam of the multi-beam or an intensity of charged particles reflected from a reflection mark provided on a stage, an amounts of adjustment calculator calculating amounts of adjustment of a reduction ratio and a rotation angle of the multi-beam based on the first beam shape, a correction map generation unit generating a first correction map in which an amount of displacement is defined that is obtained for each beam of the multi-beam based on a difference between a beam shape based on the amounts of adjustment and the first beam shape, a writing data processor generating shot data in which an amount of irradiation with each beam of the multi-beam is defined by converting writing data in which information regarding a graphic pattern to be written is defined, and correcting the amount of irradiation with each beam defined in the shot data based on the first correction map, and a controller controlling the reduction ratio and rotation angle of the multi-beam based on the amounts of adjustment.
CHARGED PARTICLE BEAM WRITING METHOD AND CHARGED PARTICLE BEAM WRITING APPARATUS
In one embodiment, a charged particle beam writing method is for writing a pattern in a writing area on a substrate by irradiating a charged particle beam onto the substrate while moving the substrate to write stripes sequentially, each of the stripes having a width W and shapes obtained by dividing the writing area by the width W. The method includes performing S times (S is an integer greater than or equal to two) strokes, each of the strokes which is a process writing the stripes in a multiplicity of 2n (n is an integer greater than or equal to one) while shifting a reference point of each of the stripes in the width direction by a preset stripe shift amount and changing a moving direction of the substrate for each of the stripes, and writing while the reference point of the stripes in the each of the strokes in the width direction of the stripes is shifted by a preset stroke shift amount in each of the strokes.
Charged particle beam writing method and charged particle beam writing apparatus
A charged particle beam writing method includes acquiring the deviation amount of the deflection position per unit tracking deflection amount with respect to each tracking coefficient of a plurality of tracking coefficients having been set for adjusting the tracking amount to shift the deflection position of a charged particle beam on the writing target substrate in order to follow movement of the stage on which the writing target substrate is placed, extracting a tracking coefficient based on which the deviation amount of the deflection position per the unit tracking deflection amount is closest to zero among the plurality of tracking coefficients, and writing a pattern on the writing target substrate with the charged particle beam while performing tracking control in which the tracking amount has been adjusted using the tracking coefficient extracted.
Method and system for determining a charged particle beam exposure for a local pattern density
A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes inputting an original set of exposure information for the area and inputting a target post-proximity effect correction (PEC) maximum dose. A local pattern density is calculated for the area of the pattern based on the original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PEC maximum dose.
Data processing method, charged particle beam writing apparatus, and charged particle beam writing system
In one embodiment, a data processing method is provided for generating writing data from design data and registering the writing data in a charged particle beam writing apparatus. The method includes generating the writing data by performing a plurality of conversion processes on a plurality of pieces of first frame data obtained through division of the design data corresponding to one chip, and performing a plurality of preprocessing processes on a plurality of pieces of second frame data obtained through division of the writing data of the chip, and registering the writing data of the chip in the charged particle beam writing apparatus. The plurality of conversion processes are performed in frame-basis pipeline processing, and the plurality of preprocessing processes are performed in frame-basis pipeline processing. The writing data is registered in the charged particle beam writing apparatus on a frame basis.