On the local injection of emitted electrons into micrograins on the surface of А$^{\mathrm{III}}$–В$^{\mathrm{V}}$ semiconductors

The characteristics of the injection of electrons into a semiconductor from a microprobe–micrograin nanogap are investigated with a tunneling microscope in the mode of field emission into locally selected surface microcrystals of indium antimonide, indium arsenide, and gallium arsenide. The current mechanisms are established and their parameters are determined by comparing the experimental I–V characteristics and those calculated from formulas of current transport. The effect of limitation of the current into the micrograins of indium antimonide and indium arsenide which manifests itself at injection levels exceeding a certain critical value, e.g., 6 $\times$ 10$^{16}$ cm$^{-3}$ for indium antimonide and 4 $\times$ 10$^{17}$ cm$^{-3}$ for indium arsenide, is discovered. A physical model, i.e., the localization of electrons in the surface area of a micrograin due to their Coulomb interaction, is proposed.