Hydrogen depth-profiling in chemical-vapor-deposited diamond films by high-resolution elastic recoil detection

We have measured the hydrogen depth profiles in chemical-vapor-deposited diamond films by elastic recoil detection. Depth resolution of $\text{∼0.23\hspace{0.05em}}\mathrm{nm}$ is achieved using a high-resolution magnetic spectrometer. The hydrogen depth profile shows a sharp peak at surface, and the hydrogen coverage is estimated to be $\text{1±0.3\hspace{0.05em}}\mathrm{ML},$ indicating formation of the monohydride structure. The surface peak has a small tail toward deeper region, which is ascribed to hydrogen atoms incorporated in a subsurface region. These subsurface hydrogen atoms might be the origin of the surface conductivity.