Wafer surface inspection method
US6724474B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2000 |
| Grant date | Apr 20, 2004 |
| Priority date | — |
| Expiry date | Mar 4, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Types of defects on a wafer are discriminated according to defect measurements obtained from a wafer inspection system which includes a plurality of dark field detectors. Using the wafer measurement system, it is determined whether first, second and third conditions are satisfied. The first condition is when a size of a defect on the wafer measured by the wafer inspection system is smaller than a limit value denoting a maximum size of crystal originated particles. The second condition is when a correlation between a plurality of defect light intensity values detected by a plurality of dark field detectors of the wafer measurement system satisfies a reference value. The third condition is when a location of the defect measured by the wafer inspection system is within a vacancy-rich area of the wafer. The type of the defect is then determined to be a crystal originated particle when the first, second and third conditions are all satisfied. On the other hand, the type of defect is determined to be an actual particle when any one or more of the first, second and third conditions is not satisfied.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.