Infuence of Ba atov adsorption and implanation of Ba-=SUP=-+-=/SUP=- ions on the electronic structure of single crystalline Ge

The effect of the adsorption Ba atoms with a thickness theta≤3-4 monolayers and implantation + ions an energy E 0 =0.5-2 keV on density states electrons in valence band, parameters bands, emission optical properties Ge(111) has been studied for first time. It is shown that during theta=1 monolayer, value thermoelectric work function φ decreases by ~ 1.9 eV, secondary electron coefficient quantum yield photoelectrons Y increases 1.5-2 times. In case =0.5 at irradiation dose D=6·10 16 cm -2 , state bands change sharply; factor 2 or more. observed changes are explained formation surface thin (~25-30 Angstrem) amorphous doped layer consisting nanoscale phases Ba-Ge type (~60-65 at.%). And excess (unbound) Ge atoms. this case, band gap g 0.3 eV. Keywords: Ion implantation, photoelectrons, efficiency, heating, gap, layer.