Patent ID: 8036447
Filing Date: 2011-10-11
Classification: G06T

Abstract:
1. A pattern inspection apparatus comprising: an image memory for storing image data obtained by photographing a semiconductor wafer on which a plurality of chips are formed; a memory controller for extracting image data from said image memory and transferring the image data; a positional deviation detecting unit for calculating a positional deviation amount between images of two areas on the semiconductor wafer to be compared; a defect discriminating unit for obtaining a differential image between the images of said two areas by using the positional deviation amount as a correction value and extracting defect candidates from the differential image; a defect analyzing unit for analyzing the images extracted as the defect candidates; and a control unit for controlling operation of the image memory, memory controller, positional deviation detecting unit, defect discriminating unit and defect analyzing unit, wherein said control unit: wherein said memory controller: