Patent · US Expired

Semiconductor device having a region doped to a level exceeding the solubility limit

US5111266A · kind A · utility

24Cited by
5References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1991
Grant dateMay 5, 1992
Priority date
Expiry dateJun 12, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D62/83

Abstract

A bipolar transistor includes a base region made of silicon crystal doped with a first impurity to a first level so as to establish a first carrier concentration in the base region and an emitter region made of silicon crystal doped with a second impurity to a second level substantially larger than the first level by a predetermined factor so as to establish a second carrier concentration in the emitter region, in which the second impurity exceeds the solubility limit of the second impurity in silicon crystal. The first and second levels are chosen in such a range that a difference in the carrier concentrations between the emitter region and the base region decreases substantially with increasing impurity level in the base region.

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