Patent ID: 11894263
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A method, comprising:
providing a workpiece comprising a substrate, a dielectric layer over the substrate, and a silicon layer over the dielectric layer;
forming a first trench and a second trench in the silicon layer, wherein the first trench and the second trench extend along a first direction;
forming a branch opening in the silicon layer, wherein the branch opening is in fluid communication with the second trench;
conformally depositing a spacer material layer over the first trench, the second trench, and the branch opening;
etching back the spacer material layer to form a spacer along sidewalls of the first trench, the second trench and the branch opening;
after the etching back, selectively removing the silicon layer between the first trench and the second trench without substantially removing the spacer and the silicon layer between the branch opening and the first trench;
after the selectively removing, transferring a pattern of the silicon layer and the spacer to the dielectric layer; and
depositing a metal layer over the dielectric layer.