Wafer inspection apparatus and wafer inspection method
US11342211B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 2018 |
| Grant date | May 24, 2022 |
| Priority date | — |
| Expiry date | Oct 10, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present disclosure provides a wafer inspection technology that involves less degradation of the image quality even when an object to be observed has a variation in height due to warpage, etc. of a wafer. This wafer inspection apparatus obtains an image with less degradation by: adjusting the focal point of an observation optical system to a height measured by a height sensor for measuring wafer surface heights; and further, correcting a switching signal for a CCD line sensor on the basis of stage position data and optical magnification data corresponding to the height so as to make a correction corresponding to the wafer surface height.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.