Semiconductor device with composite dielectric and method for fabricating the same

Abstract

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first interconnect structure disposed in a semiconductor substrate, first and second dielectric layers disposed over the semiconductor substrate, a second interconnect structure disposed in the first and second dielectric layers, and a third interconnect structure disposed in the semiconductor substrate. The first interconnect structure includes a first conductive line and a first manganese-containing layer. The second interconnect structure includes a second conductive line and a second manganese-containing layer. The third interconnect structure includes a third conductive line and a third manganese-containing layer. The third manganese-containing layer of the third interconnect structure and the first manganese-containing layer of the first interconnect structure are made of a same material.