Patent ID: 8987862
Filing Date: 2015-03-24
Classification: H01L

Abstract:
1. A method of making a device structure in an inter-level dielectric having a top surface and a bottom surface, comprising: etching a first opening through the inter-level dielectric; etching a first trench partially through the inter-level dielectric to a first depth, wherein the first trench has a first width; forming a patterned photoresist layer on the inter-level dielectric to protect the first trench from further etching; after forming the patterned photoresist layer, etching the inter-level dielectric through an opening in the patterned photoresist layer to form a second trench that extends partially through the inter-level dielectric to a second depth deeper than the first depth, wherein the second trench has a second width that is wider than the first width; removing the patterned photoresist layer; and filling the first opening, the first trench, and the second trench with conductive material.