Cs-corrected stem observation and atomic modeling of grain boundary impurities of very narrow cu interconnect

Abstract

Nano-order-analysis of grain boundary in very narrow Cu interconnect was performed for the first time using spherical aberration corrected Scanning Transmission Electron Microscope (Cs-corrected STEM). We focused our attention on both direct observation and ab initio calculation of impurities at the grain boundaries in Cu interconnect which depress the grain growth. STEM observation showed that Cl segregates at grain boundary, and that O exist in both grain boundary and interstitial. We estimated the segregation energy for the impurities at Cu grain boundary, and found that the result coincides with the observed tendency.© 2013 The Electrochemical Society.