Selective Polycrystalline Si and SiGe Deposition on Epitaxial Si Induced by B-Atomic Layer Doping

Abstract

Selective polycrystalline growth is obtained by incorporation of high level of B concentration at the interface between the Si substrate and the deposited Si layer using atomic layer doping (ALD). The high doping concentration of B at the interface is covering the crystal information of the Si lattice resulting in polycrystalline growth. B diffusion into deposited Si layer is pronounced by the transition from epitaxial Si growth to polycrystalline growth. Effective activation energy of the selective polycrystalline Si growth on Si is not different from that on SiO2. The transition from epitaxial growth to polycrystalline growth is observed for B doses in the range of 2-4×1015 cm-2 as well for selective Si as for selective Si0.8Ge0.2 growth.