Modulation Acceptor-Doping as an Alternative to Classical P-Type Impurity Doping for Silicon

Abstract

The statistical nature of impurity dopants introduced in a semiconductor leads to variability in electrical properties, posing significant challenges to device performance. This randomness becomes especially problematic as device dimensions shrink. Alternative approaches for material modification that offer precise control over the material properties, including predictable behavior at low temperatures, are essential for large-scale device integration. Modulation acceptor doping in $SiO_{2}$ was introduced as a nanoscale-doping alternative to classical impurity doping for silicon, where the carriers are spatially isolated from the dopants, resulting in a drastically reduced Coulomb scattering within silicon. In this work, the stability of the new doping method in ambient conditions is assessed. Further, a comparative analysis of impurity (p-type) doped and modulation acceptor doped Hall structures is presented. The modulation doped sample series reveals a consistent resistivity and a stable carrier density. While, the impurity-doped sample series demonstrates a lower dopant activation efficiency, higher resistivity and highlights the statistical nature of the classical method. In addition, the temperature behaviour of resistivity is studied from 300 K down to 100 K.