Deep trap levels of ion-implanted germanium in silicon measured by Schottky contact techniques

Abstract

Differential capacitance measurements on Schottky contacts can be used to determine energy level, charge, and concentration profile of ion‐implanted impurities which cause deep trap levels in the semiconducting material. For the example of germanium implanted into silicon, two deep donor levels at E_c − E₁ = 0.27 eV and E₂ − E_v = 0.51 eV are found which are due to an unstable incorporation of the implanted germanium in the silicon lattice. For the stable incorporation which is obtained at high annealing temperatures, no isoelectronic levels are found for germanium on lattice sites in silicon.