Patent ID: 7725208

Claim:
A computer-implemented method of measuring at least one manufacturing characteristic for at least one wafer from a lot of wafers manufactured by a manufacturing process, comprising: providing information representative of a set of candidate points to be measured by the manufacturing process on the at least one wafer from the lot of wafers; executing, by a computer system, a plan for performing measurements on the at least one wafer from the lot of wafers to measure the at least one manufacturing characteristic, the plan defining at least one of: which of the wafers in the lot of wafers are to be measured and which candidate points on the wafers to be measured to make measurements on; detecting one of a plurality of events or a lack of one of the plurality of events indicating a change in the manufacturing process, the change pertaining to at least one of: detecting a fault in the manufacturing process, and detecting a variation in a measurement of the at least one wafer; determining whether to take more or fewer measurements on at least one subsequent wafer in the lot of wafers to be measured based on the detected event or lack of the event; and adjusting the plan, in real time, to increase a spatial density of measurements on at least one subsequent wafer in the lot of wafers to be measured upon determining to take more measurements, and to decrease the spatial density of measurements on at least one subsequent wafer in the lot of wafers to be measured upon determining to take fewer measurements.