Patent · US Expired

Semiconductor integrated circuit device having bipolar memory, and method of manufacturing the same

US5177584A · kind A · utility

6Cited by
10References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1991
Grant dateJan 5, 1993
Priority date
Expiry dateJan 28, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/643

Abstract

A bipolar SRAM which includes a forward bipolar transistor and a reverse bipolar transistor on an identical semiconductor substrate, is disclosed. Concretely, the base region of the reverse bipolar transistor is formed at a deeper position of the substrate than the base region of the forward bipolar transistor, thereby to heighten the cutoff frequency f.sub.T of the reverse bipolar transistor.

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