کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
194740 | 459798 | 2008 | 8 صفحه PDF | دانلود رایگان |
Copper electroplating is now established as the mainstream process for filling vias and trenches in advanced interconnections schemes. A specific chemistry has been developed to achieve a complete and void free filling of the structures through “bottom-up” growth, also called “superfilling”. The acidic copper electrolyte generally contains three different organic additives (suppressor, accelerator and leveler) and chloride ions [T.P. Moffat, D. Wheeler, M. Edelstein, D. Josell, IBM J. Res. Dev. 49 (2005) 19], which play a key role for the additives adsorption and activation at the wafer surface [W.P. Dow, H.S. Huang, J. Electrochem. Soc. 152 (2005) C67]. However this chemistry leads to a rise in contamination levels incorporated within the copper films, specifically in carbon, sulfur and chlorine [A. Meunier, C. Bondoux, L. Omnès, F. Jomard, A. Etcheberry, Mater. Res. Soc. Symp. Proc. AMC (2006) 137], due to incorporation and/or degradation mechanisms. These inclusions have effects upon the film microstructure (grain size) with some time an increase of the copper film resistivity [A. Preusse, M. Nopper, AMD, Dresden, Germany, Semiconductor Fabtech 26th Edition, Wafer Processing, p. 123].Here we present a correlation studies with electrochemical quartz crystal microbalance (EQCM) measurements to provide a further insight of the adsorption of these surfactants prior and during the plating process. A study by secondary ion mass spectrometry (SIMS) which aims at better understanding the inclusion of organic by-products in the copper matrix during the plating process will also be presented. A particular emphasis will be put on the mechanisms of segregation of these species at the growing interfaces with respect to the deposition parameters.
Journal: Electrochimica Acta - Volume 53, Issue 23, 1 October 2008, Pages 7004–7011