Patent · US Expired

Semiconductor integrated circuit

US4935800A · kind A · utility

22Cited by
7References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 21, 1989
Grant dateJun 19, 1990
Priority date
Expiry dateFeb 21, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D89/00
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

This invention discloses a semiconductor integrated circuit in which an analog circuit and a digital circuit are formed on a single chip. The semiconductor integrated circuit includes a p-type semiconductor region, an n.sup.+ -type buried region formed on the p-type semiconductor region, an n-type semiconductor region formed on the n.sup.+ -type buried region, a first isolation portion, extending through the n-type semiconductor region and the n.sup.+ -type buried region and reaching the p-type semiconductor region, for isolating adjacent transistors in an analog circuit formed on the n-type semiconductor region, and a second isolation portion, formed in the n-type semiconductor region, for isolating adjacent transistors in the n-type semiconductor region.

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