Local interconnect structure and fabrication method

摘要

Local interconnect structures and fabrication methods are provided. A dielectric layer can be formed on a semiconductor substrate. A first film layer can be patterned on the dielectric layer to define a region surrounded by a local interconnect structure to be formed. A sidewall spacer can be formed and patterned surrounding the first film layer on an exposed surface portion of the dielectric layer. A second film layer can be formed on the exposed surface portion of the dielectric layer and can have a top surface substantially flushed with a top surface of the sidewall spacer. The patterned sidewall spacer can be removed to form a first opening. After forming the first opening, the dielectric layer can be etched to form a second opening through the dielectric layer. The second opening can be filled with a conductive material to form the local interconnect structure.

主权项

1. A method of making a local interconnect structure, comprising:
providing a semiconductor substrate; forming a dielectric layer on the semiconductor substrate; forming a first film layer patterned on a first surface portion of the dielectric layer; forming a sidewall spacer having a thickness only on sidewalls of the first film layer to surround the first film layer on the dielectric layer by a patterning process; further patterning the sidewall spacer by removing a portion of the sidewall spacer to expose a second surface portion of the dielectric layer and to leave a pattern made by remainng sidewall spacer; forming a second film layer on the exposed second surface portion of the dielectric layer, wherein the second film layer has a top surface substantially flushed with a top surface of the remaining sidewall spacer; removing the remaining sidewall spacer to form a first opening such that the first opening has a same pattern as the pattern of the remaining sidewall spacer; etching the dielectric layer via the first opening to expose a surface of the semiconductor substrate to form a second opening through the dielectric layer, the second opening having the same pattern; and filling the second opening with a conductive material to form a local interconnect structure having the same pattern as the pattern of the remaining sidewall spacer after the further patterning.