Effects of lateral confinement on the growth of CoSi and CoSi2 on (001)Si inside 0.2-2 mu m oxide openings prepared by electron beam lithography

Striking effects elf lateral confinement of oxide opening on the growth of CoSi and CoSi2 on silicon inside 0.2-2 mu m linear oxide openings and conta ct holes prepared by electron beam lithography were observed. The formation of CoSi at low temperature appeared to be retarded by the local compressiv e stress near the edge of linear oxide openings. A thin, uniform epitaxial CoSi2 was grown inside 0.5 mu m or smaller linear openings and 0.7 mu m or smaller contact: holes by both one-step and two-step rapid thermal annealin g processes. On the other hand, epitaxial and polycrystalline CoSi2 were fo und to form near the edges and central regions, respectively of 0.6 mu m or larger linear openings. The size effect of oxide openings is correlated to the distribution of local stress induced at the oxide edge. The relative e ase in the epitaxial growth of CoSi2 near the oxide edge of linear openings and of 0.7 mu m and smaller contact holes is attributed to the thinness of the CoSi layer. (C) 1999 Elsevier Science S.B. All rights reserved.