Method of performing multiple stage model calibration for optical imaging simulation models
A method of calibrating a simulation model of a photolithography process. The method includes the steps of defining a set of input data; defining a simulation model having model parameters which affect the simulation result produced by the simulation model; performing a first stage calibration process in which the model parameters and alignment parameters are adjusted such that the simulation result is within a first predefined error tolerance; and performing a second stage calibration process in which the alignment parameters are fixed and the model parameters are adjusted such that the simulation result is within a second predefined error tolerance.
1. A method of calibrating a simulation model of a photolithography process, said method comprising the steps of:
defining a set of input data;
defining a simulation model having model parameters which affect the simulation result produced by said simulation model;
performing a first stage calibration process in which the model parameters and alignment parameters are adjusted such that the simulation result is within a first predefined error tolerance; and
performing a second stage calibration process in which said alignment parameters are fixed and said model parameters are adjusted such that said simulation result is within a second predefined error tolerance.
2. The method of claim 1 , wherein said input data includes data defining a target pattern to be imaged and data defining an imaging process to be utilized to image said target pattern.
3. The method of claim 1 , wherein said model parameters include optical parameters and resist parameters.
4. The method of claim 1 , wherein said alignment parameters include rotation parameters, magnification parameters and translation parameters.
5. The method of claim 4 , wherein said alignment parameters are utilized to govern the alignment of the simulated image relative to the target pattern.
6. The method of claim 1 , wherein the first predefined error tolerance is greater than the second predefined error tolerance.
7. A computer readable medium configured to store program instructions for execution by a computer, said program instructions enabling a calibration process of a simulation model of a photolithography process, said calibration process comprising the steps of:
defining a set of input data;
defining a simulation model having model parameters which affect the simulation result produced by said simulation model;
performing a first stage calibration process in which the model parameters and alignment parameters are adjusted such that the simulation result is within a first predefined error tolerance; and
performing a second stage calibration process in which said alignment parameters are fixed and said model parameters are adjusted such that said simulation result is within a second predefined error tolerance.
8. The computer readable medium of claim 7 , wherein said input data includes data defining a target pattern to be imaged and data defining an imaging process to be utilized to image said target pattern.
9. The computer readable medium of claim 7 , wherein said model parameters include optical parameters and resist parameters.
10. The computer readable medium of claim 7 , wherein said alignment parameters include rotation parameters, magnification parameters and translation parameters.
11. The computer readable medium of claim 10 , wherein said alignment parameters are utilized to govern the alignment of the simulated image relative to the target pattern.
12. The computer readable medium of claim 7 , wherein the first predefined error tolerance is greater than the second predefined error tolerance.