Characterization of radiation damage induced by B and B4 ion implantation into silicon

In this study, B1- monomer and B4- cluster ions of the same boron kinetic energy level per atom (20 keV/atom) and total atomic fluence (2 × 1015 atoms/cm2) were implanted into silicon wafers held at liquid nitrogen temperature (LT, −196 °C), and followed by a two-step furnace annealing together with rapid thermal annealing treatment. The characteristics of radiation damage in both the as-implanted and as-annealed specimens were probed using Raman scattering spectroscopy (RSS) as well as transmission electron microscopy (TEM). Both the RSS and TEM results revealed that heavily-damaged and amorphous structures are formed in the as-implanted B1 and B4 specimens, respectively, mainly due to the so-called non-linear damage effect existed in the latter. Furthermore, there is less radiation damage remained in the as-annealed B4 specimens when compared to the as-annealed B1 ones, resulting from the occurrence of solid phase epitaxial growth (SPEG) in the amorphous layer of the former which thus causes significant removal of radiation damage.