With increasing integration density of LSIs, a reduction has been achieved every year in terms of the circuit line width of semiconductor devices. To form a desired circuit pattern on a semiconductor device, it is known to employ a method of transferring an original pattern formed on quarts (called a mask or a reticle when used with a stepper or a scanner, a reticle used) to a wafer using a reduction projection exposure apparatus. A high-precision original pattern is drawn using an electron beam drawing apparatus and a so-called electron beam lithography technique.
In electron beam drawing, first, a layout of a semiconductor integrated circuit is designed and layout data (design data) is generated. Thereafter, the layout data is converted to drawing data and input to an electron beam drawing apparatus. The electron beam drawing apparatus performs drawing according to the drawing data.
In the electron beam drawing, there are various phenomena that cause a dimensional change. For example, a proximity effect has an influence radius of about 10 μm, while a fogging effect or a loading effect has an influence radius of a few millimeters. In the inside of the drawing apparatus, to suppress a dimensional change due to an influence of the above, a dose correction calculation is performed in realtime.
A known example of a phenomenon that may cause a dimensional change is a proximity effect peculiar to an EUV mask having an extremely small influence radius of 300 nm to 400 nm. In a case where the dose correction calculation is performed taking into account this influence, a drawing area is divided into a mesh of about 50 nm to 100 nm, and the calculation is performed for each divided small area, which needs a huge amount of processing time for a correction calculation. It is difficult to perform such a calculation in realtime internally in the drawing apparatus, and thus it is desirable to externally calculate an amount of correction in advance and input resultant generated correction information to the drawing apparatus.
However, correction information in a map format has a large data size, which makes it difficult to efficiently transfer data. Furthermore, correction information formed in one data file is not suitable for being subjected to parallel distributed processing, which makes it difficult to efficiently perform data processing.