Modified laser-annealing process for improving the quality of electrical P-N junctions and devices
US4436557A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 1982 |
| Grant date | Mar 13, 1984 |
| Priority date | — |
| Expiry date | Feb 19, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/093
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The invention is a process for producing improved electrical-junction devices. The invention is applicable, for example, to a process in which a light-sensitive electrical-junction device is produced by (1) providing a body of crystalline semiconductor material having a doped surface layer, (2) irradiating the layer with at least one laser pulse to effect melting of the layer, (3) permitting recrystallization of the melted layer, and (4) providing the resulting body with electrical contacts. In accordance with the invention, the fill-factor and open-circuit-voltage parameters of the device are increased by conducting the irradiation with the substrate as a whole at a selected elevated temperature, the temperature being selected to effect a reduction in the rate of the recrystallization but insufficient to effect substantial migration of impurities within the body. In the case of doped silicon substrates, the substrate may be heated to a temperature in the range of from about 200.degree. C. to 500.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.