Method and system for cleaning optical elements in euv optical systems

An EUV optical system comprising:

• an EUV optical sub-system comprising:
• an illumination source configured to generate an illumination beam;
• and
• one or more optical elements configured to reflect a measurement beam, wherein the one or more optical elements are located in a collection pathway of the EUV optical sub-system;
• and
• a controller communicatively coupled to the EUV optical sub-system, the controller including one or more processors configured to execute program instructions causing the one or more processors to:
• receive design data of one or more samples;
• simulate a plurality of irradiance distributions at a plane of the EUV optical sub-system based on the design data and one or more parameters;
• aggregate the plurality of irradiance distributions to generate an aggregated irradiance distribution;
• determine a predicted contaminate distribution based on both the aggregated irradiance distribution and a contaminate growth rate, wherein the contaminate distribution is indicative of a predicted amount of contaminate deposited on the one or more optical elements;
• and
• determine a cleaning recipe for the one or more optical elements based on the predicted contaminate distribution, wherein the cleaning recipe comprises one or more cleaning processes.