Characterization of lithographic process variation for manufacturing process calibration using importance sampling

An apparatus comprising at least one computer-readable memory device storing instructions configured to cause one or more processing devices to perform operations comprising:

• selecting a modification to a lithographic process for manufacturing an integrated circuit;
• identifying structures of the integrated circuit that, when manufactured using the modified lithographic process, correspond to manufacturing failures;
• determining a likelihood ratio based, at least in part, on the modification to the lithographic process relative an unmodified lithographic process for manufacturing the integrated circuit;
• and
• utilizing the likelihood ratio to weigh the manufacturing failures of the identified structures manufactured using the modified lithographic process to characterize stochastic variation in the unmodified lithographic process for manufacturing the integrated circuit.

A system comprising:

• a memory system configured to store computer-executable instructions;
• and
• a computing system, in response to execution of the computer-executable instructions, is configured to:
• select a modification to a lithographic process for manufacturing an integrated circuit;
• identify structures of the integrated circuit that, when manufactured using the modified lithographic process, correspond to manufacturing failures;
• determine a likelihood ratio based, at least in part, on the modification to the lithographic process relative an unmodified lithographic process for manufacturing the integrated circuit;
• and
• utilize the likelihood ratio to weigh the manufacturing failures of the identified structures manufactured using the modified lithographic process to characterize stochastic variation in the unmodified lithographic process for manufacturing the integrated circuit.