Theory of Filling of High-Aspect Ratio Trenches and Vias in Presence of Additives

Numerical simulations are employed to estimate the importance of parameters such as leveling‐additive mobility and concentration on a process's capability of filling trenches or vias of a given size. Geometries relevant to ultralarge scale integration‐copper technologies are considered. Simulation results are presented within the context of a suggested experimental protocol. The importance of controlling the operating conditions is demonstrated. For example, simulations indicate that a poorly controlled additive concentration can lead to an increase in void size over that which would be obtained in an additive‐free bath. Finally, the design of robust processes is discussed in terms of the need to account for apparently random variations in the process. © 2000 The Electrochemical Society. All rights reserved.