Patent ID: 6477685
Filing Date: 2002-11-05
Classification: H01L

Abstract:
An automated wafer yield and failure analysis system, comprising:a wafer inspection instrument; a data collection means coupled to said wafer inspection instrument for collecting wafer defect data from multiple defects on wafers from said wafer inspection instrument, said wafer defect data includes x, y and z coordinates; a central database system having a means for storing wafer defect data coupled to receive said wafer defect data to compile a composite wafermap for each lot; a conversion means coupled to the wafer inspection instrument for converting the collected wafer defect data from the wafer inspection instrument from an instrument specific format to a standard format, said conversion means uses a plurality of Fast Fourier Transform equations to convert the defect data; said central database system having a means for storing converted wafer defect data patterns coupled to receive said converted wafer defect data patterns, wherein the stored converted wafer defect data patterns are retrievable based on selected criteria; a means for comparing present wafer defect data to said stored converted wafer defect data patterns to generate correlation coefficients coupled to receive said wafer defect data and said stored converted wafer defect data, wherein the correlation coefficients identify the process associated with the die failure; said converted wafer defect data pattern is stored in said central database system when correlation coefficients are within a predetermined range; and at least one user interface workstation wherein user selected converted wafer defect data can be analyzed in real time to identify the associated malfunctioning equipment.