Patent · US Expired

Semiconductor device

US4928163A · kind A · utility

16Cited by
3References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 1989
Grant dateMay 22, 1990
Priority date
Expiry dateFeb 27, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/913

Abstract

A semiconductor device formed in a semiconductor substrate and having a gate electrode formed on the semiconductor substrate, source and drain regions are formed in said the semiconductor substrate. The source and drain regions are made of a first impurity region doped with impurities of an opposite conductivity type to that of a semiconductor substrate formed at portions adjacent to the edge of the gate electrode, a second impurity region doped with impurities of an opposite conductivity type to that of a semiconductor substrate formed at portions under the first impurity region, and a third impurity region doped with impurities of opposite conductivity type to that of a semiconductor substrate formed at portions spaced apart from the edge of the gate electrode. The impurities of the second impurity region have a diffusion coefficient larger than that of the impurities of the first impurity region. The third impurity region has a higher concentration than that of the first and the second impurity regions and in addition the impurities of the third impurity region have a diffusion coefficient smaller than that of the second impurity region.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.