Ultrashallow, high doping of boron using molecular layer doping

A new doping method named molecular layer doping (MLD) is proposed. MLD is based on surface chemical adsorption of dissolvements from induced dopant gas molecules. Ultrashallow boron‐doped layers are successfully achieved by MLD using B2 H6 gas. The p+ n junction formed by MLD exhibits excellent characteristics, with a reverse bias leakage current of less than 2.5×10−16 A/μm2 at 5 V. MLD is attractive in that it offers high‐density, shallow‐junction, damage‐free, selective doping in a short time.