Boron depth distribution in iron surfaces at high-dose implantation

Due to application of lead-free materials in soldering technology, the degradation of industrial tools is accelerated. However, this can be circumvented with boriding. Two types of boride phases are usually formed (FeB and Fe2B), causing internal stress due to the different crystal structures. Our aim with B+ ion implantations is to avoid this weakness and create a single-phase iron boride layer. The ion implantation was performed at different doses (6.9.1017-1.1018 ions/cm2) of boron ions and with bombarding energies of 25 keV and 100 keV. The depth distribution of implanted boron was investigated by Secondary Neutral Mass Spectrometry (SNMS) depth profile analyses, Scanning Electron Microscopy (SEM) measurements, and by Elastic Recoil Detection Analysis (ERDA). The purpose of these measurements was to obtain information about the boron distribution produced by high-dose implantation. Our experimental analyses show that the boron distribution is more of a Pearson IV type than a Gaussian type.