Patent ID: 9012333
Filing Date: 2015-04-21
Classification: H01L

Abstract:
1. A method comprising: forming a tunnel oxide layer on a substrate; depositing via a first atomic layer deposition a first non-stoichiometric silicon nitride layer onto said tunnel oxide layer, said first non-stoichiometric silicon nitride layer comprises a first silicon richness value, said depositing comprises using a silicon precursor and a molecular nitrogen purge; reducing said first silicon richness value by a predefined amount to produce a second silicon richness value; depositing via a second atomic layer deposition a first silicon nitride layer above said first non-stoichiometric silicon nitride layer, said first silicon nitride layer comprises said second silicon richness value; reducing said second silicon richness value by another predefined amount to produce a third silicon richness value; and depositing via a third atomic layer deposition a second silicon nitride layer above said first silicon nitride layer, said second silicon nitride layer comprises said third silicon richness value.