| 摘要 |
PURPOSE:To discriminate defects by scanning a prescribed inspection area of a pattern by light beam in a lattice shape and performing measurement and feature extraction. CONSTITUTION:One side of the inspection area is made larger than the pattern line width and so smaller that two adjacent patterns may be prevented from being included, and this area is scanned in a lattice shape. At this time, the measurement and the feature extraction of a pattern are simultaneously performed every scanning line. The feature of the pattern dependent upon scanning lins is indicated by six kinds of waveform based on the permutation of ''1'' and ''0''. If a value below the reference value is obtained by the measurement dependent upon one of lattice- shaped scanning lines, the feature is inspected by the other, and the pattern is discriminated to prevent erroneous recognition. For example, when defect 4 is detected by scanning line 2, the feature is inspected by other scanning lines 31 to 34. Then, only scanning line 32 indicates feature A, so that the pattern can be difined as defective. Meanwhile, even if scanning line 2 becomes a cut line and detects a defect, feature D is indicated by all scanning lines 31 to 34, to that pattern cannot be difined as defective. Thus, patten defects can be inspected with a high precision. |
