A semiconductor device is manufactured by forming a lower structure on a substrate including first and second regions, simultaneously forming a first interconnection on the lower structure of the first region and a first portion of a second interconnection on the lower structure of the second region, forming a first interlayer insulating layer on the first interconnection and on the first portion of the second interconnection, forming a trench exposing a top surface of the first portion of the second interconnection in the first interlayer insulating layer, and forming a second portion of the second interconnection in the trench. Related structures are also disclosed.