US Patent 10234401 Method of manufacturing semiconductor devices by using sampling plans

A method of manufacturing semiconductor devices includes defining a sampling plan that contains position information about metrology sites on process wafers. A first property of the process wafers is measured to obtain measurement values at measurement points, wherein a quantity of the measurement points per process wafer is at least tenfold a quantity of the metrology sites. A sampling model that includes at least a wafer model is updated on the basis of the measurement values. The sampling plan is updated on the basis of an assessment of deviations of the measurement values from a current sampling model.