AVS 49th International Symposium
    Manufacturing Science and Technology Monday Sessions
       Session MS-MoA

Invited Paper MS-MoA1
Process Optimizations of Electrochemically Deposited Copper Films

Monday, November 4, 2002, 2:00 pm, Room C-109

Session: Control Issues in Electronics Manufacturing
Presenter: S. Shankar, Intel Corporation
Authors: H. Simka, Intel Corporation
S. Shankar, Intel Corporation
R.P. Chalupa, Intel Corporation
V.M. Dubin, Intel Corporation
Correspondent: Click to Email
Electrochemical deposition (ECD) of copper interconnects in state-of-the-art microelectronic devices currently involves the use of organic additives in the electrolyte to achieve complete feature fill with good film properties. Optimization of this complex process typically requires extensive experimental efforts and time. We present a novel model-based ECD optimization approach, which involves investigations of the physical phenomena due to additive species interactions, and shape-evolution simulations of Cu films. A new model, which accounts for the transient surface interactions of additives and their effects in deposition rate, has been developed. The model uses a boundary element method (BEM) approach to solve the species diffusion equations in the electrolyte domain, and a Eulerian-Lagrangian approach to track the growing surface. The model has been successfully applied to explain two previously published, independent datasets of copper thickness SEM profiles in ECD with multi-component additive systems. A physically consistent description of the observed fill behavior at different process conditions will be presented. Factors that are critical in achieving optimal ECD Cu deposition will be discussed, including effects of feature dimensions, Cu seed-layer coverage, and process conditions. Analysis of the seed-layer requirements for good ECD performance at various feature dimensions will also be presented.