Sub-resolution defect detection
US10935501B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 2018 |
| Grant date | Mar 2, 2021 |
| Priority date | — |
| Expiry date | Dec 6, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical metrology device, such as an interferometer, detects sub-resolution defects on a sample, i.e., defects that are smaller than a pixel in the detector array of the interferometer. The optical metrology device obtains optical metrology data at each pixel in at least one detector array and determines parameter values of a signal model for a pixel of interest using the optical metrology data received by a plurality of pixels neighboring a pixel of interest. A residual for the pixel of interest is determined using the optical metrology data received by the pixel of interest and determined parameter values for the signal model for the pixel of interest. A defect, which may be smaller than the pixel of interest can then be detected based on the residual for the pixel of interest.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.