Laser thin film poly-silicon annealing optical system
US7009140B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 2004 |
| Grant date | Mar 7, 2006 |
| Priority date | — |
| Expiry date | Nov 4, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02691
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A high energy, high repetition rate workpiece surface heating method and apparatus are disclosed which may cmprise a pulsed XeF laser operating at or above 4000 Hz and producing a laser output light pulse beam at a center wavelength of about 351 nm; an optical system narrowing the laser output light pulse beam to less than 20 μm in a short axis of the laser output light pulse beam and expanding the laser output light pulse beam to form in a long axis of the beam a workpiece covering extent of teh long axis; the optical system including a field stop intermediate the laser and the workpiece; the workpiece comprising a layer to be heated; wherein the optical system focuses the laser output light pulse beam at a field stop with a magnification sufficient to maintain an intensity profile that has sufficiently steep sidewalls to allow the field stop to maintain a sufficiently steep beam profile at the workpiece without blocking the beam profile at too high an intensity level. 2. The apparatus may also have a high average power in the laser ouput light pulse beam as delivered to the workpiece and a a linebow correction mechanism in a short axis optical assembly. The linebow correction mec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.