公开(公告)号：US20180190538A1

公开(公告)日：2018-07-05

申请号：US15854765

申请日：2017-12-27

Applicant: UNITED MICROELECTRONICS CORP. ,  Fujian Jinhua Integrated Circuit Co., Ltd.

Inventor： Hsien-Shih Chu ,  Ming-Feng Kuo ,  Yi-Wang Zhan ,  Li-Chiang Chen ,  Fu-Che Lee ,  Feng-Yi Chang

IPC: H01L21/762 ,  H01L29/06 ,  H01L21/308 ,  H01L21/02 ,  H01L21/3065

CPC classification number: H01L21/76224 ,  H01L21/02164 ,  H01L21/0217 ,  H01L21/3065 ,  H01L21/3081 ,  H01L21/3086 ,  H01L21/76229 ,  H01L29/0649

Abstract: A method of fabricating an STI trench includes providing a substrate. Later, a first mask is formed to cover the substrate. The first mask includes numerous sub-masks. A first trench is disposed between each sub-mask. Subsequently, a protective layer is formed to fill up the first trench. Then, a second mask is formed to cover the first mask. The second mask includes an opening. The sub-mask directly disposed under the opening is defined as a joint STI pattern. After that, the joint STI pattern is removed to transform the first mask into a third mask. Later, the second mask is removed followed by removing the protective layer. Finally, part of the substrate is removed by taking the third mask as a mask to form numerous STI trenches.