Method for fabricating a SONOS memory

US7951674B2 · kind B2 · utility

Assignee

• SHANGHAI IC R&D CENTER CO., LTD. · CN

Inventors

• Jun Zhu · Longbeilingcun, CN
• Ming Li · Cupertino, US

Key dates

• Filing date: Dec 28, 2009
• Grant date: May 31, 2011
• Expiry date: Dec 28, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/035

Abstract

The present invention provides a method for making SONOS memory, comprising the following steps: depositing silicon oxide layer and silicon oxynitride layer in sequence on underlayer; coating a layer of photoresist on the silicon oxynitride layer; removing part of the photoresist and form the logic area; removing silicon oxynitride layer in the logic area; removing the bottom oxide layer in the logic area; growing top oxide layer on the silicon oxynitride layer and logic area; removing the top oxide layer in the logic area; growing gate oxide layer; forming device structure of SONOS and logic area. The present invention can avoid the damage of top oxide layer and lateral etching in wet etching so as to improve the defect-free rate of devices.