Creating method of simulation model, manufacturing method of photo mask, manufacturing method of semiconductor device, and recording medium

A method of creating a simulation model, includes acquiring a CD value of a photoresist pattern actually formed based upon a test pattern, acquiring information about a shape of the photoresist pattern, acquiring an intensity distribution of an optical image based upon the test pattern by performing simulation, acquiring an empirical threshold defined according to a CD value on the intensity distribution, which corresponds to the CD value of the photoresist pattern, acquiring a parameter of the optical image based upon the intensity distribution of the optical image, acquiring a first correlation between the information about the shape of the photoresist pattern and the parameter of the optical image, acquiring a second correlation between the information about the shape of the photoresist pattern and the empirical threshold, and acquiring a third correlation between the parameter of the optical image and the empirical threshold by using first and second correlations.