| abstract |
A method for providing a highly reliable, low resistance interconnect comprises forming a trench in a dielectric layer, forming a first liner in the trench then forming a resilient layer such as a tungsten layer within the trench. The resilient layer is etched back to remove the layer from a horizontal portion of the dielectric outside the trench and to recess the layer within the trench. Next, a second liner and a copper layer are formed in the trench over the resilient layer. The copper layer and exposed portions of the two liners are polished or etched back to result in the interconnect. Variations to this embodiment are also described. |