High resistance silicon wafer and its manufacturing method
US7397110B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2003 |
| Grant date | Jul 8, 2008 |
| Priority date | — |
| Expiry date | Feb 27, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3225
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A high-resistance silicon wafer is manufactured in which a gettering ability, mechanical strength, and economical efficiency are excellent and an oxygen thermal donor is effectively prevented from being generated in a heat treatment for forming a circuit, which is implemented on the side of a device maker. A heat treatment for forming an oxygen precipitate nucleus is performed at 500 to 900° C. for 5 hours or more in a non-oxidizing atmosphere and a heat treatment for growing an oxygen precipitate is performed at 950 to 1050° C. for 10 hours or more on a high-oxygen and carbon-doped high-resistance silicon wafer in which resistivity is 100 Ωcm or more, an oxygen concentration is 14×1017 atoms/cm3 (ASTM F-121, 1979) or more and a carbon concentration is 0.5×1016 atoms/cm3 or more. By these heat treatments, a remaining oxygen concentration in the wafer is controlled to be 12×1017 atoms/cm3 (ASTM F-121, 1979) or less. Thus, there is provided a high-resistance, low-oxygen and high-strength silicon wafer in which resistivity is 100 Ωcm or more and an oxygen precipitate (BMD) having a size of 0.2 μm is formed so as to have high density of 1×104/cm2 or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.