Metal capacitors with damascene structures and method for forming the same

Claim 1

A metal capacitor with damascene structures, comprising: a first Cu wire and a second Cu wire disposed in a first insulator; a second insulator having an opening disposed on the first insulator, wherein the opening is positioned on the first Cu wire; a stop layer disposed on the second insulator, wherein the opening in the second insulator is extended to the stop layer; a first metal layer conformally disposed in the opening and contacting the surface of the first Cu wire; a dielectric layer conformally disposed on the first metal layer in the opening; a second metal layer conformally disposed on the dielectric layer in the opening; a third insulator disposed on the stop layer and the second metal layer; a first Cu damascene structure and a second Cu damascene structure disposed in the second and third insulators and the stop layer, wherein the first Cu damascene structure is composed of a third Cu wire and a first Cu plug and the second Cu damascene structure is composed of a fourth Cu wire and a second Cu plug, wherein the second metal layer is connected with the third Cu wire through the first Cu plug, and the fourth Cu wire is connected with the second Cu wire through the second Cu plug; a first sealing layer disposed between the second Cu wire and the second insulator; and a second sealing layer disposed on the third and fourth Cu wires.

Claim 10

A method for forming a metal capacitor with damascene structures, comprising: providing a first insulator; forming a first Cu wire and a second Cu wire in the first insulator; forming a first sealing layer at least on the first and second Cu wires; forming a second insulator on the first sealing layer; forming a stop layer on the second insulator; forming an opening exposing the first Cu wire in the stop layer, the second insulator and the first sealing layer; conformally forming a first metal layer on the stop layer in the opening; conformally forming a dielectric layer on the first metal layer; conformally forming a second metal layer on the dielectric layer; removing the first metal layer, the dielectric layer and the second metal layer to expose the stop layer; forming a third insulator on the stop layer and the second metal layer; forming dual damascene patterns included trenches and holes in the third insulator, the stop layer and the second insulator; forming a third Cu wire and a fourth Cu wire in the trenches and a first Cu plug and a second Cu plug in the holes, wherein the second metal layer is connected with the third Cu wire through the first Cu plug, and the fourth Cu wire is connected with the second Cu wire through the second Cu plug; and forming a second sealing layer at least on the third and fourth Cu wires.

Claim 11

A method for forming a metal capacitor with damascene structures, comprising: providing a first insulator; forming a first Cu wire and a second Cu wire in the first insulator; forming a first sealing layer at least on the first and second Cu wires; forming a second insulator on the first sealing layer; forming a stop layer on the second insulator; forming an opening exposing the first Cu wire in the stop layer, the second insulator and the first sealing layer; conformally forming a first metal layer on the stop layer in the opening; conformally forming a dielectric layer on the first metal layer; conformally forming a second metal layer on the dielectric layer; removing the first metal layer, the dielectric layer and the second metal layer to expose the stop layer; forming a third insulator on the stop layer and the second metal layer; forming dual damascene patterns included trenches and holes in the third insulator, the stop layer and the second insulator; forming a third Cu wire and a fourth Cu wire in the trenches and a first Cu plug and a second Cu plug in the holes, wherein the second metal layer is connected with the third Cu wire through the first Cu plug, and the fourth Cu wire is connected with the second Cu wire through the second Cu plug; and forming a second sealing layer at least on the third and fourth Cu wires.