Method and apparatus of pattern recognition
US5568563A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | May 3, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A pattern recognition apparatus and method in which a set is produced which includes a fundamental pattern vector on a basis place and other fundamental pattern vectors of the patterns displaced from the fundamental pattern on the basis place. Then a subspace spanned by fundamental pattern vectors included in the set is generated. A test pattern vector of a wafer to be inspected is projected to the subspace and similarity between the fundamental vectors and the test pattern vector is measured. Further, an image is used after it is filtered by a normalization filter. Furthermore, sensitivity of pattern recognition is varied by changing the dimension of the pattern vectors. Moreover, for objects expressed by numerical values which can not be compared directly, the data of the objects are transformed into images and, then, a set of fundamental pattern vectors are worked out.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.