| 摘要 |
PURPOSE:To obtain a high missing detecting sensitivity in a short time by measuring a virtual pattern of a straight line and a regular square of an external form of an inspection object, and a geometrical distance of the external form of the inspection object, so that an evaluation function is generated from its result. CONSTITUTION:A picture data of a semiconductor chip of an inspection object caught by a television camera 21 is processed by a processing circuit 22 and a software, and stored in an external form data file 23. Subsequently, a coordinate is read out successively from the file 23, and a geometrical feature of the semiconductor chip is derived by a computer 24. Next, basing on the geometrical feature of said semiconductor chip, a normal pattern is supposed, and a position shift in the X, Y and Q directions from its virtual pattern is calculated. When executing its calculation, it is executed so that the decision is performed by separating the part to which the polarity of a shift from the normal pattern is connected by positive, and the part to which said polarity is connected by negative, respectively. In this way, the inspection can be executed exactly. |
