Theory of tetrahedral-site interstitials- andp-bonded impurities in Si

Abstract

A theory of the major chemical trends in the deep-energy levels of interstitial defects at the tetrahedral site in semiconductors is developed, based on a simple, empirical tight-binding scheme. The importance of hyperdeep and hyperbonding levels is emphasized. The theory is applied to various charge states of 29 interstitial defects in Si with the use of a self-consistent defect potential. The theory accounts for the electron-nuclear double-resonance data of the deep ${\mathrm{Al}}^{2+}$ wave function and the deep-energy levels of ${\mathrm{Al}}^{+}$, as well as for what is currently known about the major chemical trends in the deep and shallow levels of several other impurities.