Appl. Phys. Lett. 97, 253101 (2010); http://dx.doi.org/10.1063/1.3527078 (3 pages)

Reactive solid-state dewetting of Cu–Ni films on silicon

Raphael Clearfield¹, Justin G. Railsback¹, Ryan C. Pearce^1,2, Dale K. Hensley³, Jason D. Fowlkes³, Miguel Fuentes-Cabrera³, Michael L. Simpson^2,3, Philip D. Rack^2,3, and Anatoli V. Melechko¹

¹Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA
²Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
³Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA

(Received 25 August 2010; accepted 22 November 2010; published online 20 December 2010)

The behavior of a 50 nm Cu–Ni alloy film on Si in a process of reactive solid-state dewetting is presented. The films were annealed at a range of temperatures (300–700 °C) in 1% H₂ 99% N₂ reducing atmosphere. The resulting alloy and silicide particles formed by film dewetting and film reaction with the substrate were distinguished by selective wet etching and examined by scanning electron microscopy and spectroscopy. After potassium hydroxide etch, regions that etch slower than silicon substrate have distribution statistics similar to the alloy and silicide particles prior to their removal, indicating strong coupling between mass transport across the interface and along the surface.