A study of the mobility and trapping of minor hydrogen concentrations in diamond in three dimensions using quantitative ERDA microscopy

Two direct and two indirect nuclear methods are used for the analysis of hydrogen in diamond of different types. Exploiting the power of two-dimensional position sensitive detectors, the distribution of hydrogen in and on diamond in three dimensions has been measured by elastic recoil detection analysis, supplementing the earlier resonant nuclear techniques. Indirect methods of muonium spin rotation and time differential perturbed angular distribution measurements prove to be very informative. In a series of dynamic experiments, hydrogen has been implanted and the diffusion thereof sought as a function of temperature. Unlike the equivalent case for silicon, no migration of the hydrogen in diamond is found up to 1473 K. This striking result is considered in regard to existing theoretical calculations. It is concluded that the implanted hydrogen is self-trapped. Arguments are presented as to the location of hydrogen in natural diamond, in diamond grown at high pressure and high temperature, and in diamond grown by chemical vapour deposition.