发明名称 |
Etching method for forming a square cornered polysilicon wordline electrode |
摘要 |
A split gate FET wordline electrode structure and method for forming the same including an improved polysilicon etching process including providing a semiconductor wafer process surface comprising first exposed polysilicon portions and adjacent oxide portions; forming a first oxide layer on the exposed polysilicon portions; blanket depositing a polysilicon layer on the first exposed polysilicon portions and adjacent oxide portions; forming a hardmask layer on the polysilicon layer; carrying out a multi-step reactive ion etching (RIE) process to etch through the hardmask layer and etch through a thickness portion of the polysilicon layer to form second polysilicon portions adjacent the oxide portions having upward protruding outer polysilicon fence portions; contacting the semiconductor wafer process surface with an aqueous HF solution; and, carrying out a downstream plasma etching process to remove polysilicon fence portions.
|
申请公布号 |
US6921695(B2) |
申请公布日期 |
2005.07.26 |
申请号 |
US20030685127 |
申请日期 |
2003.10.14 |
申请人 |
TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD. |
发明人 |
OUYANG HSIU;LO CHI-HSIN;HUANG CHEN-MING;HSIEH CHIA-TA;TSAI CHIA-SHIUNG |
分类号 |
H01L21/311;H01L21/3213;H01L21/336;H01L21/8247;H01L27/115;(IPC1-7):H01L21/336 |
主分类号 |
H01L21/311 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|