Control of misoriented grains and pinholes in CoSi₂ grown on Si(001)

Abstract

Two types of growth conditions have been obtained that consistently overcome the formation of epitaxially misoriented grains in CoSi2/Si(001). One is by codeposition of Co and Si at Co-rich ratios at a substrate temperature of {reversed tilde} 500°C. This method yields films of low resistivity (16 μΩ cm) and low ion channeling minimum yield (χmin ≈ 2%), but the misfit dislocation densities are of the order of 105 cm-1. The second way uses a template method of growth after an epitaxial Si buffer layer. Films grown this way have somewhat higher resistivities than those grown by the first method, but have lower misfit dislocation densities. The strain relief mechanism in these films also appears to be different from that of codeposited films. Pinhole densities in films grown by both methods are below our detection limit of 103 cm-2. © 1991.