Patent · US Expired

Technique for forming an oxide/nitride layer stack by controlling the nitrogen ion concentration in a nitridation plasma

US6723663B1 · kind B1 · utility

16Cited by

7References

23Claims

0Family size

Assignee

Advanced Micro Devices, Inc. · US

Inventors

Karsten Wieczorek · Dresden, DE
Falk Graetsch · Dresden, DE
Lutz Herrmann · Hamburg, DE

Key dates

Filing date	May 22, 2003
Grant date	Apr 20, 2004
Priority date	—
Expiry date	May 22, 2023

Classification

Technology area (CPC H)Electricity
CPC primaryH01L21/02271
WIPO fieldSemiconductors
WIPO sectorElectrical engineering

Abstract

For aggressively scaled field effect transistors, nitrogen is incorporated into a base oxide layer, wherein, at an initial phase of a plasma nitridation process, the nitrogen ion density is maintained at a value so that incorporation of nitrogen into the channel region is minimized. Subsequently, when the thickness of the base oxide layer has increased, due to residual oxygen in the plasma ambient, the nitrogen ion density is increased, thereby increasing the nitridation rate. Preferably, the nitrogen ion density is controlled by varying the pressure of the plasma ambient. Moreover, a system is disclosed that allows control of the nitridation rate in response to an oxide layer thickness.

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