Damage removal and boron diffusion during solid phase epitaxial growth of SiGe alloy layers

Abstract

SiGe/Si heterostructures have been fabricated using germanium ion implantation into silicon and subsequent solid phase epitaxy (SPE) growth. The damage removal and boron diffusion in the SiGe/Si heterostructures formed by high-dose Ge + preamorphized and BF 2 + implanted Si(0 0 1) during SPE growth have been investigated by double-crystal X-ray diffraction (DCXRD) and secondary ion mass spectrometry (SIMS). The results show that annealing at 600°C for 60 min can only remove a little damage induced by implantation and nearly no redistribution of Ge and B atoms has occurred during the annealing. Most damage induced by Ge + and BF 2 + ion implantation have been removed after annealing at 950°C for 60 min and accompanied by Ge diffusion, a boron diffusion has taken place. When annealing temperature rose to 1050°C, Ge diffusion has been slight while B diffusion has been deeper into the Si substrate with a very good distribution. The X-ray diffraction (0 0 4) rocking curves from the samples annealed at 1050°C for 60 min display two SiGe peaks, which may be related to the B and Ge concentration profiles.