摘要 |
The invention provides a SONOS structure, a manufacturing method thereof and a semiconductor device with the SONOS structure. The SONOS structure comprises: a first tunneling oxide layer formed on a substrate, a charge storage silicon nitride layer, a second silicon oxide layer, a thin graded silicon nitride layer having graded Si/N content formed on the second silicon oxide layer, a third silicon oxide layer formed on the thin graded silicon nitride layer, and a polysilicon control gate. The Si/N content ratio of the silicon nitride of the thin graded silicon nitride layer increases gradually, wherein the silicon nitride of the graded silicon nitride layer closer to the second silicon oxide layer contains higher nitride content, and the silicon nitride of the graded silicon nitride layer closer to the third silicon oxide layer contains higher silicon content.
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