Title :
Microstructure and electromigration in copper damascene lines
Author :
Arnaud, Laurent ; Tartavel, G. ; Berger, T. ; Mariolle, D. ; Gobil, Y. ; Touet, I.
Author_Institution :
LETI CEA-G, Grenoble, France
Abstract :
Grain sizes and crystallographic orientations of Cu were analyzed versus line width in damascene Cu interconnects. Pure bamboo lines were not obtained because grain size decreased as line width was reduced. Comparison of electromigration results for wide line CVD Cu (3 μm) polycrystalline structures and narrow line (0.5 μm) quasi-bamboo structures provided almost the same activation energy Ea~0.65 eV, even though the (200) texture has rotated in the film plane for the narrow damascene lines. These results are in agreement with copper diffusion involving a slow self surface diffusion or located at the interface between Cu and SiO2. PVD Cu samples showed a better activation energy value Ea=1.02 eV
Keywords :
CVD coatings; copper; crystal orientation; electromigration; grain size; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; integrated circuit testing; sputtered coatings; surface diffusion; surface texture; 0.5 micron; 0.65 eV; 1.02 eV; 3 micron; Cu crystallographic orientation; Cu grain size; Cu(200) texture rotation; Cu-SiO2; Cu-SiO2 interface diffusion; PVD Cu samples; activation energy; bamboo lines; copper damascene lines; copper diffusion; damascene Cu interconnects; electromigration; grain size; line width; microstructure; narrow damascene lines; narrow line Cu quasi-bamboo structures; slow self surface diffusion; wide line CVD Cu polycrystalline structures; Adhesives; Atherosclerosis; Copper; Crystallography; Electromigration; Grain boundaries; Grain size; Microelectronics; Microstructure; Tin;
Conference_Titel :
Reliability Physics Symposium Proceedings, 1999. 37th Annual. 1999 IEEE International
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-5220-3
DOI :
10.1109/RELPHY.1999.761624
