Energy Transfer between Excited Adsorbed Dye Molecules and Charged Defects in Insulator-Semiconductor Structures

Abstract

Two competition channels of energy migration of electronically excited dye molecules adsorbed on the germanium and silicon oxidized surfaces are discovered. In the low adsorbed dye-molecules concentration range the excitation energy is mainly consumed for discharging of negatively and positively charged oxide layer traps. Energy distribution of the traps is qualitatively determined. Their charging is accompanied with red shift of the dye molecules fluorescence maximum. Excitation energy dissipation in adsorption phase dominated if the adsorbed molecules concentration is high enough.