Exploring the Electronic Properties of Individual Gold NPs on n-type Si Surfaces

We demonstrate the controlled deposition of isolated gold nanoparticles (Au-NPs) on the surface of n-Si substrates and the electrical charge effect. Au-NPs were dispersed in the citrate solution which were spin coated on a highly cleaned n-Si substrate. The isolated NPs were verified by means of AC imaging mode of atomic force microscope (AFM). Subsequently the electrical measurements were performed using the conductive mode of AFM (C-AFM). The consecutive sweeps of the I-V measurements on a particular NP exhibited a change in the reverse tunneling current profile. This indicates a trapped charge effect in the Au-NP.