Patent · US Expired

Semiconductor device having a protective transistor

US5449939A · kind A · utility

42Cited by
2References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 27, 1994
Grant dateSep 12, 1995
Priority date
Expiry dateDec 27, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D89/711

Abstract

A semiconductor device has an internal circuit, an output transistor and a protective transistor for protecting the output transistor and the internal circuit against an ESD-induced destruction caused by a surge pulse entering from an input/output terminal. The sum of a first distance between a contact for connecting an input/output terminal with the collector of the protective transistor and a field oxide film and a second distance between a contact for connecting the input/output terminal with the emitter of the protective transistor and the field oxide film overlying the base of the laterally formed protective transistor is made smaller than the sum of a third distance between a contact for connecting the input/output terminal with the drain of the output transistor and the gate electrode of the output transistor and a fourth distance between a contact for connecting a potential line with the source of the output transistor and the gate electrode of the output transistor. Besides, the effective channel length of the output transistor is made longer than the effective base width of the protective transistor.

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