Method and apparatus for doping silicon wafers using a solid dopant source and rapid thermal processing
US5550082A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1995 |
| Grant date | Aug 27, 1996 |
| Priority date | — |
| Expiry date | Mar 30, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B31/02
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention is, in part, a new process for dopant diffusion, both p-type (e.g., B) and n-type (e.g., P, As), into silicon wafers, using rapid thermal processing (RTP). It uses a surface layer of a new planar dopant as an active dopant source. Such a source is produced using either a rigid holder wafer with a spin-on dopant or CVD doped oxides deposited on its surface, or such a source is high pressure planar solid source having a surface that has been activated by dry etching or sputtering etching. Such a dopant source is placed in proximity to a processed silicon wafer in such a manner that its active surface is facing the surface of the silicon wafer during RTP. Both the silicon wafer and the dopant source are heated by lamps emitting light causing transport of dopant from the dopant source to the silicon surface. The dopant source may be produced using either silicon wafers, quartz or ceramic plates or planar solid diffusion sources which are commercially available in a form of solid discs containing compounds containing various dopant atoms (e.g., B, P, and As).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.