Patent · US Expired

Device with asymmetrical channel dopant profile

US6025224A · kind A · utility

27Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 1997
Grant dateFeb 15, 2000
Priority date
Expiry dateMar 31, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/905
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for fabricating a bit line junction in a DRAM array device which improves the doping profile in the channel region. The method includes contradoping via ion implantation through the bit line contact opening made in the device during processing. This particular doping method increases the concentration of dopants in the channel region on the bit line side of the array, without a corresponding increase of dopants on the buried strap side. Such a doping profile results in an improvement in the off current behavior of the device. Depending on the aspect ratio of the contact opening, tilt angles for the ion implantation are possible and can be adjusted for maximum off current efficiency.

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