Spatially resolved measurement of lattice damage in alpha‐particle‐irradiated type IIa natural diamond by confocal photoluminescence microscopy

Confocal fluorescence microscopy has been used to measure the three‐dimensional distribution of the H3 color center produced in type IIa natural diamonds by 5 MeV He+ irradiation at a total fluence of 8×1015 cm−2. The peak of the H3 emission occurs 16 μm below the surface of the irradiated side of the diamond, which is in fair agreement with the peak of the vacancy distribution predicted by a Monte Carlo calculation (transport of ions in matter or trim). The H3 distribution is broader in the direction normal to the surface (10 μm full width at half maximum) than the trim calculation. This is attributed to diffusion of vacancies caused by self‐annealing during irradiation.