Patent · US Expired

Method of fabricating semiconductor devices having a diffused region of reduced length

US4567641A · kind A · utility

21Cited by
8References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 12, 1984
Grant dateFeb 4, 1986
Priority date
Expiry dateSep 12, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D64/668
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An improved semiconductor device having a diffused region of reduced length and an improved method of fabricating such a semiconductor device are disclosed. The semiconductor device may be a MOSFET or an IGR, by way of example. In a form of the method of fabricating a MOSFET, an N.sup.+ SOURCE is diffused into a P BASE through a window of a diffusion mask. An anisotropic or directional etchant is applied to the N.sup.+ SOURCE through the same window. The etchant removes most of the N.sup.+ SOURCE, but allows shoulders thereof to remain intact. These shoulders, which form the completed N.sup.+ SOURCE regions, are of reduced length, greatly reducing the risk of turn-on of a parasitic bipolar transistor in the MOSFET. The risk of turn-on of a parasitic bipolar transistor in an IGR is similarly reduced, when the IGR is fabricated by the improved method.

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