With the development of the micro-processing, silicon material technique, the silicon structural design, mass production,
the scientific researches on integrated circuit have been developed rapidly. Defect detection and fault diagnosis as critical
design requirements is necessary to achieve high-quality, cost-effective multichip systems. An increasingly difficult task,
however, is the inherent need to accurately locate, indentify the defects within the microchip. A method of defect
detection of IC wafer have been investigated using mathematical morphology. Firstly, the differential charts of the
pending images and the intact image of IC wafer are computed and digitized to two gray levels, i.e. black and white.
Secondly, the brightness of the pending images have been transformed to the same brightness as that of intact image in
order to make the arithmetics is robust for various illumination conditions. Next, the defects on the binary image of
differential chart can be found and dealt with mathematical morphology. Finally, several representative characteristics
are proposed to extract and describe the defects of IC wafer image, for example perimeter, area, macro axis, minor axis,
eccentricity ratio, centroid, circularity and rectangular degree, etc.