Observation of individual dopants in a thin silicon layer by low temperature Kelvin Probe Force Microscope

Detection of individual dopants in the thin silicon layer using Kelvin Probe Force Microscopy is presented. The analysis of the surface potential images taken at low temperatures (13K) on n-type and p-type samples reveals local potential fluctuations that can be attributed to single phosphorus and boron atoms, respectively. Results are confirmed by simulation of surface potential induced by dopants and by the back gate voltage dependence of the measured potential.