Silicon semiconductor substrate and preparation thereof
US7208043B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2002 |
| Grant date | Apr 24, 2007 |
| Priority date | — |
| Expiry date | Aug 22, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12674
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A silicon semiconductor substrate has a structure possessing oxygen precipitate defects fated to form gettering sites in a high density directly below the defect-free region of void type crystals. The silicon semiconductor substrate is formed by heat-treating a silicon semiconductor substrate derived from a silicon single crystal grown by the Czochralski method or the magnetic field-applied Czochralski method and characterized by satisfying the relational expression (Oi DZ)−(COP DZ)≦10 μm wherein Oi DZ denotes a defect-free zone of oxygen precipitate crystal defects and COP DZ denotes a region devoid of a void type defect measuring not less than 0.11 μm in size, and having not less than 5×108 oxygen precipitate crystal defects per cm3. The method for making the substrate comprises the steps of deriving a silicon semiconductor substrate from a silicon single crystal grown by the Czochralski method or the magnetic field-applied Czochralski method using molten silicon containing not less than 5×1017 atoms and not more than 1.5×1019 atoms of nitrogen per cm3 and heat-treating the silicon semiconductor substrate in a non-oxidizing atmosphere at a highest final temperature of not lower t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.