Dielectric Barrier in the Subtractive Process of Formation of a Copper Metallization System

This article studies various methods for the formation of dielectric diffusion barriers between open areas of copper and an organosilicate low-k dielectric in the subtractive method of forming a metallization system, in which metal lines are first formed, and then a low-k dielectric is deposited. Films of dense and porous organosilicate glass deposited by chemical deposition from solutions are used as a low-k dielectric. A comparison is made between AlN barrier layers formed by atomic layer deposition and SiCN barriers deposited by plasma-assisted chemical vapor deposition. The successful formation of a model structure of copper metallization using AlN barriers is demonstrated.