Patent ID: 8643124

Claim:
A method of forming a semiconductor device, comprising: forming a tunnel oxide layer on a silicon containing layer of a substrate; forming a multi-layer charge storing layer by: depositing on the tunnel oxide layer a first charge storing layer comprising an oxygen-rich oxynitride in which a stoichiometric composition of the oxygen-rich oxynitride results in the first charge storing layer being substantially trap free; and depositing directly on the first charge storing layer a second charge storing layer comprising an oxygen-lean, silicon-rich and nitrogen-rich oxynitride layer in which a stoichiometric composition of the oxygen-lean, silicon-rich and nitrogen-rich oxynitride layer results in it being trap dense, and wherein the second charge storing layer further comprises a concentration of carbon selected to increase a number of traps therein; forming a blocking oxide layer on the second oxynitride layer; and forming a silicon containing gate layer on the blocking oxide layer.