Scatterometer and method of scatterometry using acoustic radiation
US11536654B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2020 |
| Grant date | Dec 27, 2022 |
| Priority date | — |
| Expiry date | Mar 11, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/102
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An acoustic scatterometer has an acoustic source operable to project acoustic radiation onto a periodic structure and formed on a substrate. An acoustic detector is operable to detect the −1st acoustic diffraction order diffracted by the periodic structure and while discriminating from specular reflection (0th order). Another acoustic detector is operable to detect the +1st acoustic diffraction order diffracted by the periodic structure, again while discriminating from the specular reflection (0th order). The acoustic source and acoustic detector may be piezo transducers. The angle of incidence of the projected acoustic radiation and location of the detectors and are arranged with respect to the periodic structure and such that the detection of the −1st and +1st acoustic diffraction orders and discriminates from the 0th order specular reflection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.