Tuning a process controller based on a dynamic sampling rate

A system, comprising:

• a process tool operable to fabricate workpieces in accordance with a process;
• a metrology tool operable to collect metrology data associated with a subset of workpieces processed in the process tool, the collecting exhibiting an irregular pattern;
• a tuning unit operable to receive metrology data associated with a selected state observation for a selected run of the process and determine a tuning factor for the selected run based on the irregular pattern;
• and
• a process controller operable to discount the selected state observation based on the determined tuning factor, generate a state estimate of the process based on the discounted selected state observation, and control the process tool based on the state estimate.

A system for estimating a state of a process implemented by a tool for fabricating workpieces, comprising:

• means for collecting metrology data associated with a subset of workpieces processed in the tool, the collecting exhibiting an irregular pattern;
• means for receiving metrology data associated with a selected state observation for a selected run of the process;
• means for determining a tuning factor for the selected run based on the irregular pattern;
• means for discounting the selected state observation based on the determined tuning factor;
• means for generating a state estimate of the process based on the discounted selected state observation;
• and
• means for controlling at least one process tool operable to implement the process based on the state estimate.