Pd-vacancy complex in Si identified with the perturbed angular correlation technique

Abstract

A Pd-vacancy $(\mathrm{Pd}\text{\ensuremath{-}}{\mathrm{V}}^{\ensuremath{-}})$ complex in Si has been identified with the perturbed angular correlation technique using the radioactive $^{100}\mathrm{Pd}$ probe produced by recoil implantation. The fraction of Pd probes in the complex has been determined as a function of dopant type (B, P, As, and Sb), dopant concentration $({10}^{15}--6\ifmmode\times\else\texttimes\fi{}{10}^{19}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3})$ and annealing temperature $(21--500\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C})$. The $\mathrm{Pd}\text{\ensuremath{-}}{\mathrm{V}}^{\ensuremath{-}}$ complex, with a unique interaction frequency of $13.1(2)\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, was observed only in ${n}^{+}\text{\ensuremath{-}}\mathrm{Si}$ with a maximum relative fraction of $\ensuremath{\sim}52%$ achieved between $200--300\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ while a broad distribution of interaction frequencies was apparent in $n$-, $p$-, and ${p}^{+}\text{\ensuremath{-}}\mathrm{Si}$. Annealing beyond $300\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ yielded a reduction in the $\mathrm{Pd}\text{\ensuremath{-}}{\mathrm{V}}^{\ensuremath{-}}$ fraction with a dissociation energy of $2.5(7)\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$. Density functional theory calculations of the electric field gradient for the given defect configuration were consistent with a measured value of $3.58\ifmmode\times\else\texttimes\fi{}{10}^{21}\phantom{\rule{0.3em}{0ex}}\mathrm{V}∕{\mathrm{m}}^{2}$.