Phosphorous doping a semiconductor particle
US5926727A · kind A · utility
Inventors
Key dates
| Filing date | Dec 11, 1995 |
| Grant date | Jul 20, 1999 |
| Priority date | — |
| Expiry date | Dec 11, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E10/50
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method (10) of phosphorus doping a semiconductor particle using ammonium phosphate. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried (16, 18), with the phosphorus then being diffused (20) into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.