A method for very low fluence implantations using Rutherford scattering

A simple method for extremely low fluence ion implantation is described. It is based on implanting ions which are Rutherford backscattered (RBS) from a thin gold layer into the desired target. This method enables ion implantations to be carried out, as are needed to realize quantum centers on the atomic scale to serve as qubits and other nano sized devices. The required implantation fluences are orders of magnitude below the commonly-used current integration capabilities; hence control on the implanted fluence is usually complicated. The described method enables control on the implanted fluence even when extremely low. The dependence of the energy and fluence of scattered ions on the angle and scattering target thickness is analyzed by using SRIM simulations. These are verified for the case of N scattering implantation by direct counting in a surface barrier detector and for the case of Xe by counting the tracks that scattered and implanted Xe ions leaved in HOPG as viewed by scanning probe microscopy.