Patent · US Expired

Vertical bipolar SRAM cell, array and system, and a method of making the cell and the array

US5896313A · kind A · utility

22Cited by
7References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 2, 1997
Grant dateApr 20, 1999
Priority date
Expiry dateJun 2, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/406
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An SRAM memory cell is provided in which a pair of cross-coupled n-type MOS pull-down transistors are coupled to respective parasitically formed bipolar pull-up transistors. The memory cell is formed within a semiconductor layer which extends over a buried layer. The bipolar transistors are formed parasitically from the buried layer and the semiconductor layer used to form the pull-down transistors. The bases of the bipolar transistors may also be dynamically controlled. An SRAM memory array having a plurality of such memory cells and a computer system incorporating the SRAM memory array are also provided.

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