METHOD OF FABRICATING SEMICONDUCTOR DEVICES ON A GROUP IV SUBSTRATE WITH CONTROLLED INTERFACE PROPERTIES AND DIFFUSION TAILS

摘要

A multi junction solar cell having epitaxially-deposited III/V compounds on vicinal group IV substrates and method for making same. The solar cell includes an AlAs nucleating layer on a Ge substrate. The group IV substrate contains a p-n junction whose change of characteristics during epitaxial growth of As-containing layers is minimized by the AlAs nucleating layer. The AlAs nucleating layer provides improved morphology of the solar cell and a means to control the position of a p-n junction near the surface of the group IV substrate through diffusion of As and/or P and near the bottom of the III/V structure through minimized diffusion of the group IV element.