Patent · US Expired

Longitudinal MISFET manufacturing method, longitudinal MISFET, semiconductor storage device manufacturing method, and semiconductor storage device

US7244977B2 · kind B2 · utility

4Cited by
11References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 10, 2002
Grant dateJul 17, 2007
Priority date
Expiry dateOct 10, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/903

Abstract

A semiconductor memory device includes a vertical MISFET having a source region, a channel forming region, a drain region, and a gate electrode formed on a sidewall of the channel forming region via a gate insulating film. In manufacturing the semiconductor memory device, the vertical MISFET in which leakage current (off current) is less can be realized by: counter-doping boron of a conductivity type opposite to that of phosphorus diffused into a poly-crystalline silicon film (10) constituting the channel forming region from an n type poly-crystalline silicon film (7) constituting the source region of the vertical MISFET, and the above-mentioned poly-crystalline silicon film (10); and reducing an effective impurity concentration in the poly-crystalline silicon film (10).

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