Patent · US Expired

Method for forming a MOSFET with substrate source contact

US5023196A · kind A · utility

37Cited by
10References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1990
Grant dateJun 11, 1991
Priority date
Expiry dateJan 29, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/168
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A MOSFET having a back-side source contact and top-side gate and drain contacts is provided by a structure comprising superposed N.sup.+, N-,P-, N.sup.+ regions arranged between top and bottom surfaces of the semiconductor die. In a preferred implementation, two trenches are etched from the top surface to the P-, N.sup.+ interface. A buried P-, N.sup.+ short is provided in one trench and a gate dielectric and gate electrode are provided over the sidewall P- region exposed in the other trench. This creates a vertical MOSFET in which the N.sup.+ substrate forms the source region shorted to the P- body region in which the channel is created by the gate. Superior performance is obtained in RF grounded-source circuit applications.

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