Method and apparatus for modeling an apodization effect in an optical lithography system

A computer readable storage device storing instructions that when executed by a computer cause the computer to perform a method for accurately predicting an apodization effect in an optical lithography system for manufacturing an integrated circuit, the method comprising:

• collecting an apodization effect induced spatial transmission profile from the optical lithography system;
• constructing an apodization model based on the spatial transmission profile, which involves fitting an enhanced Gaussian model based on the spatial transmission profile, wherein the enhanced Gaussian model is proportional to e−C(ρ·σ)n, wherein ρ is a normalized radial position, σ and n are fitting parameters, σ is the Gaussian Sigma, n controls an attenuation rate of a transmission coefficient, and C is a predetermined positive value;
• and
• enhancing a lithography model for the optical lithography system by incorporating the apodization model into the lithography model,
• wherein the enhanced lithography model accurately predicts the effects of apodization on the optical lithography system.

An apparatus that accurately predicts an apodization effect in an optical lithography system for manufacturing an integrated circuit, comprising:

• a collecting mechanism configured to collect an apodization effect-induced spatial transmission profile from the optical lithography system;
• a constructing mechanism configured to construct an apodization filter model based on the spatial transmission profile, which involves fitting an enhanced Gaussian model based on the spatial transmission profile, wherein the enhanced Gaussian model is proportional to e−C(ρ·σ)n, wherein ρ is a normalized radial position, σ and n are fitting parameters, σ is the Gaussian Sigma, n controls an attenuation rate of a transmission coefficient, and C is a predetermined positive value;
• and
• an incorporating mechanism configured to enhance a lithography model for the optical lithography system by incorporating the apodization model into the lithography model, wherein the enhanced lithography model accurately predicts the effects of apodization on the optical lithography system.