International Business Machines Corporation
Tall trenches for via chamferless and self forming barrier

Abstract:

Chamferless via structures and methods of manufacture are provided. The structures include a conductive line and a set of chamferless wiring vias formed in a dielectric material with at least one of the vias in contact with the conductive line. The set of chamferless wiring vias is formed with at least a first subset of wiring vias of a first height and a second subset of wiring vias of a second height. The method includes filling trenches within a substrate with a conductive material to form a set of wiring vias with a first height. Next, a block mask is used over a capping material layer to expose a portion of the conductive material layer. The capping material and the conductive material of the set of wiring vias defined by the block mask are etched forming a subset of wiring vias of the second height.