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.

A charged particle beam optical apparatus has a plurality of irradiation optical systems each of which irradiates an object with a charged particle beam and a first control apparatus configured to control a second irradiation optical system on the basis of an operation state of a first irradiation optical system.

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 data processing method is for processing data in a writing apparatus performing multiple writing by using multiple beams. The data is for controlling an irradiation amount for each beam. The method includes generating irradiation amount data for each of a plurality of layers, the irradiation amount data defining an irradiation amount for each of a plurality of irradiation position, and the plurality of layers corresponding to writing paths in multiple writing, performing a correction process on the irradiation amounts defined in the irradiation amount data provided for each layer, calculating a sum of the irradiation amounts for the respective irradiation positions defined in the corrected irradiation amount data, comparing the sums between the plurality of layers, and determining whether or not an error has occurred in the correction process based on the comparison result.

In one embodiment, a multi charged particle beam writing apparatus includes a blanking plate including a plurality of blankers, bitmap generation processing circuitry generating bitmap data for each writing pass of multi-pass writing, the bitmap data specifying irradiation time periods for a plurality of irradiation positions, a plurality of dose correction units configured to receive bitmap subdata items obtained by dividing the bitmap data from the bitmap generation processing circuitry, and correct the irradiation time periods to generate a plurality of dose data items corresponding to respective processing ranges, and data transfer processing circuitry transferring the plurality of dose data items to the blanking plate through a plurality of signal line groups. Each of the signal line groups corresponds to the blankers located in a predetermined region of the blanking plate. The data transfer processing circuitry changes the signal line groups, used to transfer the plurality of dose data items generated by the respective dose correction units, for each writing pass.

In some embodiments, data is received defining a plurality of shot groups that will be delivered by a charged particle beam writer during an overall time period, where a first shot group will be delivered onto a first designated area at a first time period. A temperature of the first designated area at a different time period is determined. In some embodiments, the different time period is when secondary effects of exposure from a second shot group are received at the first designated area. In some embodiments, transient temperatures of a target designated area are determined at time periods when exposure from a shot group is received. An effective temperature of the target area is determined, using the transient temperatures and applying a compensation factor based on an amount of exposure received during that time period. A shot in the target shot group is modified based on the effective temperature.

A method for mask process correction or forming a pattern on a reticle using charged particle beam lithography is disclosed, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern, and where pattern exposure information is modified to increase edge slope of the reticle pattern where sensitivity of the wafer pattern is high. A method for fracturing or mask data preparation is also disclosed, where pattern exposure information is determined that can form a pattern on a reticle using charged particle beam lithography, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, and where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern.

In a method of manufacturing a photo mask for lithography, circuit pattern data are acquired. A pattern density, which is a total pattern area per predetermined area, is calculated from the circuit pattern data. Dummy pattern data for areas having pattern density less than a threshold density are generated. Mask drawing data is generated from the circuit pattern data and the dummy pattern data. By using an electron beam from an electron beam lithography apparatus, patterns are drawn according to the mask drawing data on a resist layer formed on a mask blank substrate. The drawn resist layer is developed using a developing solution. Dummy patterns included in the dummy pattern data are not printed as a photo mask pattern when the resist layer is exposed with the electron beam and is developed.

In a method of manufacturing a photo mask for lithography, circuit pattern data are acquired. A pattern density, which is a total pattern area per predetermined area, is calculated from the circuit pattern data. Dummy pattern data for areas having pattern density less than a threshold density are generated. Mask drawing data is generated from the circuit pattern data and the dummy pattern data. By using an electron beam from an electron beam lithography apparatus, patterns are drawn according to the mask drawing data on a resist layer formed on a mask blank substrate. The drawn resist layer is developed using a developing solution. Dummy patterns included in the dummy pattern data are not printed as a photo mask pattern when the resist layer is exposed with the electron beam and is developed.

A method of adjusting a critical dimension of a reticle patterns in a reticle used to fabricate semiconductor devices can include determining respective values for a critical dimension of a plurality of reticle patterns in an image of the reticle and providing an atmospheric plasma to a first reticle pattern included in the plurality of reticle patterns, the first reticle pattern having a first value for the critical dimension that is different than a target value for the critical dimension. The atmospheric plasma may not be provided to second reticle patterns included in the plurality of reticle patterns, the second reticle patterns having a second value for the critical dimension that is about equal to the target value.