Patent · US Expired

Process for fabricating a bipolar transistor with a thin base and an abrupt base-collector junction

US4523370A · kind A · utility

58Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 5, 1983
Grant dateJun 18, 1985
Priority date
Expiry dateDec 5, 2003

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/092
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A process for fabricating a bipolar transistor with a thin base and an abrupt base-collector junction includes the steps of depositing a thin layer of polycrystalline or amorphous silicon base material in a single crystal collector region, while in-situ doping the deposited silicon with boron atoms, and thereafter, recrystallizing the deposited silicon layer by thermal-pulse annealing at a temperature high enough to effect recrystallization and solid phase epitaxial regrowth while low enough to minimize interdiffusion of dopants between the base and collector. The process further includes providing the transistor fabricated by the aforedescribed steps with an abrupt base-emitter junction. This is accomplished by depositing n.sup.++ doped polysilicon with a LPCVD process and thereafter thermal annealing the polysilicon.

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