Process for manufacturing semiconductor devices by implantation and diffusion
US4771009A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 17, 1987 |
| Grant date | Sep 13, 1988 |
| Priority date | — |
| Expiry date | Feb 17, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/2255
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for manufacturing semiconductor devices according to the present invention comprises a step for thermally oxidizing semiconductor substrates (1), (12), to form first and second oxide films (24), (25) on one main surface and on another main surface thereof, respectively; a step for selectively implanting impurity inons via said first oxide film (24) to form elements in said semiconductor substrates (1), (12); a step for successively forming a film (30) that constitutes a source of impurity diffusion and a protective film (31) on said second oxide film (25); and a step of common heat-treatment for forming predetermined diffused layers (17), (18) on said one main surface of said semiconductor substrates (1), (12) by diffusing at least one kind of the impurity ions that are implanted, and for forming a diffused layer on said another main surface of the semiconductor substrates (1), (12) by diffusing impurities contained in the film (30) that constitutes said source of impurity diffusion into said semiconductor substrates (1), (12) via said second oxide film (25). This makes it possible to effectively remove impurity atoms such as heavy metals present in the semiconductor subs…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.