Three dimensional hydrogen microscopy in diamond

We introduce proton-proton scattering at a microprobe of 17 MeV protons to quantitatively image three dimensional hydrogen distributions in polycrystalline diamond at a lateral resolution better than 1 m and high sensitivity. The images show that most of the hydrogen of a 110-textured undoped polycrystalline diamond film is located at grain boundaries. The average amount of hydrogen is (8.1±1.5)·1014 atoms/cm2 along the grain boundaries which corresponds to about a third of a monolayer. The content within the grain is below the detection limit of 1.4-1016 atoms/cm2 (0.08 at-ppm).