Abstract: A method for detecting sequential processing effects on integrated circuits to be manufactured in a manufacturing process, includes: determining a first random sequence for a plurality of wafers; performing a first process step on the plurality of wafers by a first process tool in accordance with the first random sequence; determining a second random sequence for the plurality of wafers; and performing a second process step on the plurality of wafers by a second process tool in accordance with the second random sequence. The method performs randomization of wafer processing sequences at the process tool itself. By performing randomization of wafer processing sequences at the process tool, the need for separate wafer handlers is eliminated, resulting in significant cost reduction, clean-room space savings, improved yield, improved manufacturing cycle time, and improved signal-detection capabilities.

Abstract: A defect categorization method is described. Two or more regions are defined on a die. These regions can be repeated for other dies on the same wafer or corresponding regions on other dies on other wafers. The wafer(s) are scanned for defects. The location of each defect, along with any other desired defect data is stored. The stored defect data is then categorizing by region or regions within a die. As a result of the categorization, optional defect generation predictions can be made or optional yield or kill ratio predictions can be made. Also, specific regions(s) can be rescanned based on the result of the categorization.

Abstract: A method and apparatus for detecting random layout structures sensitive to process induced pattern errors in semiconductor device manufacturing applies a first manufacturing process to a first wafer containing semiconductor devices. A second manufacturing process is applied to a second wafer containing semiconductor devices. The second manufacturing process is similar to, but different from the first manufacturing process. The first and second wafers are compared by image subtraction to detect systematic pattern defects in the semiconductor devices of one of the first and second wafers. After differences are detected, the layout is examined to determine whether the difference represents a defect. If so, the design rules of the layout can be changed to accommodate a wider process variation and improve processing yield.

Abstract: A method of determining classification codes for defects occurring in semiconductor manufacturing processes and for storing the information used to determine the classification codes. A wafer is selected from a production lot after the lot is sent through a first manufacturing process. The selected wafer is scanned to determine if there are defects on the wafer. Images of selected defects are examined and a numerical value is assigned to each of N elemental descriptor terms describing each defect. A classification code is determined for each defect based upon the numerical values assigned to the N elemental descriptor terms. The classification code and numerical values assigned to the N elemental descriptor terms are stored in a database. The wafer is sent through each sequential process and classification codes are assigned to additional defects selected after each sequential process.