This study described a novel and original method of ultra-shallow fluorine and nitrogen implantation from radio
frequency (RF = 13,56MHz) CF4 and NH3 plasmas, performed in classical RIE / PECVD reactors. The performed
experiments indicate that ultra-shallow implantation of high concentration of fluorine and nitrogen ions by using r.f.
plasma reactors (PECVD ad RIE) is feasible. It is also possible to control the implantation process parameters, ie
implantation depth and maximum concentration, by controlling the parameters of the plasma processes.
Electrical characterization of MOS structures with HfO2 layer as a gate dielectric, shows that samples implanted with
nitrogen, have the best insulating properties, better even the reference sample. Samples prepared by fluorine
implantation, exhibit much worse I-V behavior for low, medium and high electric fields, than all samples studied in this
article. This samples exhibit the highest leakage currents, too.