Charge-controlled fixation of DNA molecules on silicon surface and electro-physical properties of Au-DNA-Si interface

► Conditions of DNA fixation on surface of n-type silicon crystal were investigated. ► In darkness immobilizing of molecules leads to form DNA ropes. ► Fixation under illumination results in forming of single DNA mesh. ► Different types of DNA conformations result in different types of interface states. ► Estimations of interface state densities are presented.