发明授权
- 专利标题: Split-gate flash cell
- 专利标题(中): 分离式闪存单元
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申请号: US09208913申请日: 1998-12-10
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公开(公告)号: US06309928B1公开(公告)日: 2001-10-30
- 发明人: Hung-Cheng Sung , Di-Son Kuo , Chuang-Ke Yeh , Chia-Ta Hsieh , Yai-Fen Lin , Wen-Ting Chu
- 申请人: Hung-Cheng Sung , Di-Son Kuo , Chuang-Ke Yeh , Chia-Ta Hsieh , Yai-Fen Lin , Wen-Ting Chu
- 主分类号: H01L21336
- IPC分类号: H01L21336
摘要:
A novel method of forming a first polysilicon gate tip (poly-tip) for enhanced F—N tunneling in split-gate flash memory cells is disclosed. The poly-tip is formed in the absence of using a thick polysilicon layer as the floating gate. This is made possible by forming an oxide layer over the poly-gate and oxidizing the sidewalls of the polygate. Because the starting thickness of polysilicon of the floating gate is relatively thin, the resulting gate beak, or poly-tip, is also necessarily thin and sharp. This method, therefore, circumvents the problem of oxide thinning encountered in scaling down devices of the ultra large scale integration technology and the fast programmability and erasure performance of EEPROMs is improved.