Method of fabricating dielectric layer

摘要

A method of fabricating a dielectric layer is provided. A first oxide layer is formed on a polysilicon layer. A silicon-rich nitride layer is formed on a first oxide layer. A silicon-poor nitride layer is formed on the silicon-rich nitride layer. An oxidation step is performed on the silicon-poor nitride layer. A second oxide layer is formed on the silicon-poor nitride layer. The dielectric layer comprising a multiple nitride layer structure is formed.