초록 ▼

A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of

A method is described for characterizing defects on a test surface of a semiconductor wafer using a confocal-microscope-based automatic defect characterization (ADC) system. The surface to be tested and a reference surface are scanned using a confocal microscope to obtain three-dimensional images of the test and reference surfaces. The test and reference images are converted into sets of geometric constructs, or "primitives," that are used to approximate features of the images. Next, the sets of test and reference primitives are compared to determine whether the set of test primitives is different from the set of reference primitives. If such a difference a exists, then the difference data is used to generate defect parameters, which are then compared to a knowledge base of defect reference data. Based on this comparison, the ADC system characterizes the defect and estimates a degree of confidence in the characterization.

대표청구항 ▼

[ What is claimed is:] [1.]1. A method of locating defects on a test surface, wherein the test surface is contained within a test volume represented by a Cartesian coordinate system having x, y, and z axes describing a set of unique x-y-z coordinates, the method comprising the steps of:scanning the

[ What is claimed is:] [1.]1. A method of locating defects on a test surface, wherein the test surface is contained within a test volume represented by a Cartesian coordinate system having x, y, and z axes describing a set of unique x-y-z coordinates, the method comprising the steps of:scanning the test surface in the test volume with a focused beam so that the focal point of the focused beam coincides, in turn, with each unique x-y-z coordinate within the test volume, the test surface being part of a semiconductor wafer;determining, for each column of points specified by a unique x-y coordinate in the test volume, a measured characteristic of the focused beam;storing all the measured characteristics to form an array of test data representing a two-dimensional mapping of the test surface;extracting a set of test primitives from the test data, the test primitives representing boundaries of features on the test surface; andcomparing the set of test primitives with a set of reference primitives to determine whether the set of test primitives is different the set of reference primitives.