Enhanced oxynitride gate dielectrics using NF3 gas

Claim 1

A semiconductor manufacturing process comprising: providing a semiconductor substrate, wherein said semiconductor substrate comprises single crystal silicon; immersing said semiconductor substrate into an oxidation chamber maintained at a first temperature between 400° and 700° C. for a first duration, said oxidation chamber comprising a first ambient gas selected from the group consisting of N 2 and Argon; subsequent to said immersing, introducing a second ambient gas comprising a first fluorine species into said oxidation chamber to remove a residual oxide from said semiconductor substrate and to form a fluorine terminated upper surface of said semiconductor substrate; subsequent to said introducing a second ambient gas, ramping the ambient temperature within said oxidation chamber to a second temperature in the range of approximately 600° to 950° C.; introducing a nitrogen-free, fluorine-free third ambient gas comprising oxygen into said oxidation chamber to form a base oxide layer on said fluorine terminated upper surface of said semiconductor substrate, wherein said base oxide layer is substantially free of nitrogen; introducing a fourth ambient gas comprising oxygen, nitrogen, and a second fluorine species into said oxidation chamber to form an oxynitride layer by reoxidizing said base oxide layer; forming a conductive gate structure on said oxynitride layer; and introducing a source/drain impurity distribution into a pair of source/drain regions laterally displaced on either side of a channel region of said semiconductor substrate wherein said channel region is aligned with said conductive gate.

Claim 18

A method of forming a dielectric upon a semiconductor surface comprising: removing a residual oxide from an upper surface of said semiconductor substrate in a fluorine bearing ambient such that a fluorine terminated upper surface is formed, wherein said removing is performed in a chamber at 400° to 700° C.; ramping up the chamber temperature to 600° to 950° C.; forming a base oxide layer substantially free of nitrogen by exposing the upper surface to a nitrogen-free, fluorine-free ambient; and reoxidizing said base oxide layer in a reoxidizing ambient comprising nitrogen, oxygen, and fluorine to form an oxynitride layer.

Claim 19

A method of forming a dielectric upon a semiconductor surface comprising: removing a residual oxide from an upper surface of said semiconductor substrate in a fluorine bearing ambient such that a fluorine terminated upper surface is formed, wherein said removing is performed in a chamber at 400° to 700° C.; ramping up the chamber temperature to 600° to 950° C.; forming a base oxide layer substantially free of nitrogen by exposing the upper surface to a nitrogen-free, fluorine-free ambient; and reoxidizing said base oxide layer in a reoxidizing ambient comprising nitrogen, oxygen, and fluorine to form an oxynitride layer.