Abstract:
A method for aligning a first set of features of a fabrication level of an integrated circuit chip to an electron beam alignment target including a high atomic weight layer formed in a substrate and forming the first set of features using electron beam lithography and for aligning a second set of features of the same fabrication level of the integrated circuit chip to an optical alignment target formed in the substrate and forming the second set of features using photolithography, the optical alignment target itself is aligned to the electron beam alignment target. Also a method of forming and a structure of the electron beam alignment target.
Abstract:
A contact metallurgy structure comprising a patterned dielectric layer having cavities on a substrate; a suicide or germanide layer such as of cobalt and/or nickel located at the bottom of cavities; a contact layer comprising Ti or Ti/TiN located on top of the dielectric layer and inside the cavities and making contact to the suicide or germanide layer on the bottom; a diffusion barrier layer located on top of the contact layer and inside the cavities; optionally a seed layer for plating located on top of the barrier layer; a metal fill layer in vias is provided along with a method of fabrication. The metal fill layer is electrodeposited with at least one member selected from the group consisting of copper, rhodium, ruthenium, iridium, molybdenum, gold, silver, nickel, cobalt, silver, gold, cadmium and zinc and alloys thereof. When the metal fill layer is rhodium, ruthenium, or iridium, an effective diffusion barrier layer is not required between the fill metal and the dielectric. When the barrier layer is platable, such as ruthenium, rhodium, platinum, or iridium, the seed layer is not required.