Patent · US Expired

FETs having lightly doped drain regions that are shaped with counter and noncounter dorant elements

US6180470A · kind A · utility

7Cited by
18References
42Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 19, 1996
Grant dateJan 30, 2001
Priority date
Expiry dateDec 19, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/925
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Lifetime of a short-channel NMOS device is increased by modifying distributions of electrically active LDD dopant at boundaries of the device's LDD regions. The LDD dopant distributions are modified by implanting counter-dopants at the boundaries of the LDD regions. Group III counter-dopants such as boron and group IV elements such as silicon alter activation properties of the LDD dopant. The dopant distributions are modified at the device's n-junctions to reduce the maximum electric field displacement at an interface defined by the device's gate and substrate. The dopant distributions can be further modified to shape the n-junctions such that hot carriers are injected away from the gate.

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