| 摘要 |
Disclosed is a method for cutting a line top end of a fin structure for a double-pattern fin field effect transistor. A fin structure is formed first by means of silicon nitride hard mask lines, and then the photoetching and etching process for the fin line top end cutting is conducted; at the moment, the required cutting depth is relatively great, so that the etching has sufficient time and space to adjust etching menus to balance the etching rate at each level, such as a planarization layer SOC, silicon nitride, silicon dioxide and a silicon substrate, so that the bottom appearance at the cut position is smoother and the fin structure is finally formed, and generation of silicon protrusions and silicon cones is avoided in the process of etching, so as to improve electric performance of the device. |
