Method of manufacturing a semiconductor device
US4375999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1981 |
| Grant date | Mar 8, 1983 |
| Priority date | — |
| Expiry date | Feb 13, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/923
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of manufacturing a semiconductor device for simultaneously forming a plurality of diffused regions of selectively different diffusion depths, comprises forming polycrystalline semiconductor layers of corresponding, selectively different depths on the semiconductor substrate surface provided with a diffusion mask having a plurality of diffusion windows. By the impurity diffusion into the substrate through the windows at the polycrystalline semiconductor layer interface with the substrate, a comparatively shallow diffused region and a comparatively deep diffused region are formed simultaneously by a single diffusion process, respectively, under the comparatively thick polycrystalline semiconductor layer and the comparatively thin polycrystalline semiconductor layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.