Abstract: A Method for inspecting flat objects, especially wafers, with an object surface, comprises the steps of: scanning a digital image with a plurality of image points of said object surface with color- or grey values for each of said image points; detecting defects on said object surface by comparing said scanned digital image to a digital reference image; defining and selecting corresponding portions in said scanned digital image and in the digital reference image; determining a representative color- or grey value for each of said selected portions; calculating a compare value from said representative color- or grey value of said scanned digital image of a portion and a representative color- or grey value of said digital reference image of the same portion; and correcting each image point of said scanned digital image with a correction value determined from said compare value of step (e).

Abstract: An inspection system for flat objects, especially wafers and dies, comprising: a handling system for loading objects into the inspection system; a sensor assembly for receiving images or measuring values of the object surface or parts of the object surface; a driving assembly for generating a relative movement between the objects and the sensor assembly, where a movement is effected between objects relative to the sensor assembly along a first trajectory; wherein at least one further sensor assembly is provided, and the driving assembly is adapted to generate a further relative movement, where a movement of different objects relative to the sensor assembly can be generated on at least a second trajectory in order to allow at least two objects to be treated simultaneously.

Abstract: A Method for inspecting flat objects , especially wafers, with an object surface, comprises the steps of: scanning a digital image with a plurality of image points of said object surface with color- or grey values for each of said image points; detecting defects on said object surface by comparing said scanned digital image to a digital reference image; defining and selecting corresponding portions in said scanned digital image and in the digital reference image; determining a representative color- or grey value for each of said selected portions; calculating a compare value from said representative color- or grey value of said scanned digital image of a portion and a representative color- or grey value of said digital reference image of the same portion; and correcting each image point of said scanned digital image with a correction value determined from said compare value of step (e).