Method to incorporate, and a device having, oxide enhancement dopants using gas immersion laser doping (GILD) for selectively growing an oxide layer
US5885904A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1997 |
| Grant date | Mar 23, 1999 |
| Priority date | — |
| Expiry date | Feb 14, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02255
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a uniform and reliable oxide layer on the surface of a semiconductor substrate using projection gas immersion laser doping (P-GILD) is provided. A semiconductor substrate is immersed in an oxide enhancing compound containing atmosphere. The oxide enhancing compound containing atmosphere may include phosphorus, arsenic, boron or an equivalent. A 308 nm excimer laser is then applied to a portion of the substrate to induce incorporation of the oxide enhancing compound into a portion of the substrate. The deposition depth is dependent upon the strength of the laser energy directed at the surface of the substrate. A uniform and reliable oxide layer is then formed on the surface of the substrate by heating the substrate. The laser may be applied with a reflective reticle or mask formed on the substrate. An E.sup.2 PROM memory cell having a program junction region in a silicon substrate is also provided. An oxide layer is positioned between a program junction and a floating gate. The oxide layer is formed by a single or multiple thermal oxidation step(s) to have at least a first oxide thickness due to a GILD oxide enhancing compound underlying a region of the oxide ha…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.