Patent ID: 7496478

Claim:
A method of providing information for controlling a semiconductor manufacturing process by monitoring a semiconductor manufacturing trend by using wafer test measurements and providing information for responding to said trend, the method comprising: acquiring test measurements; receiving the wafer test measurements; calculating a product yield percentage, the product yield percentage being an average of a set of yields from a selected number of wafers tested; selecting a parametric parameter having an upper specification limit and a lower specification limit; determining a storage percentile for a certain wafer, wherein the determining of the storage percentile is performed using a set of measurements of the parametric parameter for the certain wafer, wherein the storage percentile is equal to the product yield percentage if a number of the set of measurements greater than the upper specification limit exceeds a number of the set of measurements lower than the lower specification limit, and wherein the storage percentile is equal to the product yield percentage subtracted from one hundred percent if the number of the set of measurements less than the lower specification limit exceeds the number of the set of measurements greater than the upper specification limit; designating a predetermined number of spatial regions on the certain wafer; obtaining a first group of measurements from the set of measurements for a first spatial region of the spatial regions; storing a measurement from the first group of measurements closest to the storage percentile; and providing the stored measurements taken over time for use as criteria for controlling the semiconductor manufacturing process.