Verfahren zum Herstellen einer Multischichtenverbindungsstruktur.

摘要

A process for forming a connection between two layers of a multilayer interconnection in a semiconductor device comprises the steps of: forming a first conductive layer 3; forming on the first conductive layer a layer 4 for preventing stress- and/or electro-migration of the conductive layer; forming an opening 8 through the entire thickness of the migration-preventing layer 4, the opening having a diameter less than the width of the conductive layer, to expose the surface of the conductive layer; forming an interlayer insulating layer 9,11 on the migration-preventing layer 4 and the exposed surface of the conductive layer 3 to cover the layers and to fill the opening 8; forming a through-hole 6 having a diameter less than that of the opening in the insulating layer 9,11 to the surface of the conductive layer, the through-hole 6 lying entirely within the region of the filled opening so that the surface of the conductive layer is exposed but the periphery of the opening 8, i.e. the remaining part 41,42 of the migration-preventing layer 4, is not exposed; and forming a second conductive layer 15 on the interlayer insulating layer so that, during the formation of the second conductive layer, the through-hole 6 is filled with the conductive substance of said conductive layer 15 thereby electrically to connect the first and the second conductive layers. Since the periphery of the opening 8 is not exposed, an undercut of the subsequently formed through-hole 6 due to faster etching of the layer 4 is avoided, reducing the danger of contamination of the conductive connection.