Abstract: A method includes measuring a first overlay error between a first process layer and a second process layer using a first overlay target formed on the second process layer. A second overlay error between the first process layer and a third process layer is measured using a second overlay target formed on the third process layer. At least one parameter of an operating recipe for performing a photolithography process on the first process layer is determined based on the first and second overlay error measurements. A system includes a metrology tool and a controller. The metrology tool is configured to measure a first overlay error between a first process layer and a second process layer using a first overlay target formed on the second process layer and measure a second overlay error between the first process layer and a third process layer using a second overlay target formed on the third process layer.

Abstract: A processing line includes a processing tool, a metrology tool, a processing monitor, and a sampling controller. The processing tool is configured to process workpieces. The metrology tool is configured to measure an output characteristic of selected workpieces in accordance with a sampling plan. The processing monitor is configured to monitor the processing of at least one workpiece in the processing tool to generate a fingerprint and determine a processing metric based on the fingerprint. The sampling controller is configured to receive the processing metric and determine the sampling plan for the metrology tool based on the processing metric. A method for processing workpieces includes processing a plurality of workpieces in a processing tool. A characteristic of selected workpieces is measured in accordance with a sampling plan. The processing of at least one workpiece in the processing tool is monitored to generate a fingerprint. A processing metric is determined based on the fingerprint.