Laser thermal annealing of lightly doped silicon substrates
US7494942B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2006 |
| Grant date | Feb 24, 2009 |
| Priority date | — |
| Expiry date | Nov 21, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2101/40
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for performing laser thermal annealing (LTA) of a substrate using an annealing radiation beam that is not substantially absorbed in the substrate at room temperature. The method takes advantage of the fact that the absorption of long wavelength radiation (1 micron or greater) in some substrates, such as undoped silicon substrates, is a strong function of temperature. The method includes preheating a portion of the substrate to a critical temperature where the absorption of long-wavelength annealing radiation is substantial, and then irradiating the portion of the substrate with the annealing radiation to generate a temperature capable of annealing the portion of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.