Patent ID: 7740991
Filing Date: 2010-06-22
Classification: B82Y,H01J

Abstract:
1. A beam dose computing method of a writing apparatus, comprising: specifying, with a control unit of the writing apparatus, a matrix of rows and columns of regions as divided from a surface area of a target object to include first, second and third regions of different sizes, the third regions being less in size than the first and second regions; determining, with the control unit of the writing apparatus, first corrected doses of a charged particle beam for correcting fogging effects in the first regions; determining, with the control unit of the writing apparatus, corrected size values for correcting pattern line width deviations occurring due to loading effects in the second regions; using said corrected size values in said second regions to create a map of base doses of the beam in respective ones of said second regions; storing the map of base doses of the beam in a memory; using said corrected size values to prepare a map of proximity effect correction coefficients in respective ones of said second regions; storing the map of proximity effect correction coefficients in said memory; inputting the maps from said memory, and using the maps to determine second corrected doses of said beam for correction of proximity effects in said third regions; and using the first and second corrected doses to determine an actual beam dose at each position on the surface of said object.