Silicon wafer
US10648101B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 24, 2017 |
| Grant date | May 12, 2020 |
| Priority date | — |
| Expiry date | Feb 24, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F77/703
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A silicon wafer includes a denuded zone which is a surface layer and of which the density of vacancy-oxygen complexes which are complexes of vacancies and oxygen is less than 1.0×1012/cm3. An intermediate layer is disposed inwardly of the denuded zone so as to be adjacent to the denuded zone. The density of the vacancy-oxygen complexes in the intermediate layer increases gradually inwardly in the depth direction from the boundary with the denuded zone within a range of 1.0×1012/cm3 or over and less than 5.0×1012/cm3. The intermediate layer has a depth determined corresponding to the depth of the denuded zone. A bulk layer is disposed inwardly of the intermediate layer so as to be adjacent to the intermediate layer. The density of the vacancy-oxygen complexes in the bulk layer is 5.0×1012/cm3 or over.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.