GROWTH OF EPITAXIAL COSI2 ON (100)SI

A bilayer CoSi2/TiN has been grown on (100)Si, starting from a (100) p-type Si wafer deposited with thin layers of Ti followed by Co metal, through a two-stage annealing in a nitrogen environment and an intervening etch. In this process, Co and Ti switch places to form CoSi2 covered with TiN on Si. Cross-section transmission electron microscopy, and Rutherford backscattering/channeling spectrometry were used to characterize the bilayer sample. The CoSi2 was found to be single crystal, fully coherent, and epitaxial with (100)Si, whereas the TiN at the top of CoSi2 was polycrystalline. The stress in the CoSi2/TiN layer was found to be 1.9 X 10(10) dynes/cm2. The planar (100) CoSi2/Si interface was interrupted with {111} ledges which are believed to be structural ledges present to maintain the coherency at the interface.