Reactive epitaxy of Co nanoparticles on (111)Si

The formation of epitaxial CoSi2 islands of nanoscopic dimensions is reported using the technique of reactive cluster deposition. Co clusters in the size range 5-50 nm were synthesized by sputtering of a high purity Co target inside a ultra high vacuum (UHV) sputtering chamber, using the technique of inert gas condensation. The clusters were then deposited on the reconstructed Si (111) surface. Upon annealing, the particles reacted with the Si substrate to form epitaxial CoSi2. Our observations were made using a JEOL 200CX transmission electron microscope modified for in situ sputtering and UHV conditions.