ORIENTED GROWTH OF CU(110) ON YSI2-X(1(1)OVER-BAR-00/SI(100) AND DIFFUSION BEHAVIOR IN COPPER SILICIDE FORMATION

The growth and diffusion characterization of Cu films on the YSi2-x(1100BAR)/Si(100) substrate are studied. On the YSi2-x(1100BAR) layer prepared using a thin template layer, highly oriented Cu(110) film growth is observed, and Cu diffusion through the YSi2-x layer and the subsequent Cu3Si formation occur at temperatures as low as 200-degrees-C. On the contrary, the growth of Cu with normal orientation is evident on the YSi2-x layer with poor epitaxial quality, and the out-diffusion of Si forms a CU3Si layer on the YSi2-x layer. The film growth on YSi2-x layers is discussed on the basis of the lattice match between superlattice cells of Cu and YSi2-x, and the diffusion behavior is interpreted in terms of relaxation of the affinity of Cu for Si.