Title :
Modeling of stress evolution of electroplated Cu films during self-annealing
Author :
Huang, Rui ; Robl, Werner ; Detzel, Thomas ; Ceric, Hajdin
Author_Institution :
Kompetenzzentrum Automobil-und Industrieelektron. (KAI) GmbH, Villach, Austria
Abstract :
Electroplated Cu films are known to change their microstructure at room temperature due to the self-annealing effect. This recrystallization process results in a film-thickness-dependent stress evolution. Films with the thickness of 5μm and below decrease in stress with time, while thicker films reveal initially an increase in film stress followed by a stress relaxation at a later stage. This behavior is explained by the superposition of grain growth and grain size dependent yielding. Existing models have been used and improved to describe the mechanisms related to stress evolution. In general, the models proposed in this study provide a satisfactory description of the stress evolution of electroplated Cu films and the simulated results show good agreement with the experimental data. This gives the possibility to evaluate and predict mechanical behavior of electroplated Cu films at room temperature.
Keywords :
copper; electroplating; grain growth; grain size; internal stresses; metallic thin films; recrystallisation; recrystallisation annealing; stress analysis; stress relaxation; yield stress; Cu; electroplated Cu films; film-thickness-dependent stress evolution; grain growth; grain size; microstructure; recrystallization process; self-annealing; size 5 mum; stress evolution modeling; stress relaxation; temperature 293 K to 298 K; Contracts; Copper; Economic forecasting; Grain size; Microstructure; Power generation economics; Temperature; Tensile stress; Thermal conductivity; Thermal resistance; Cu films; modeling; self-annealing; stress;
Conference_Titel :
Reliability Physics Symposium (IRPS), 2010 IEEE International
Conference_Location :
Anaheim, CA
Print_ISBN :
978-1-4244-5430-3
DOI :
10.1109/IRPS.2010.5488706