Dynamical behaviour of implanted ions in diamond

Carbon-13 ions were implanted into natural type IIa diamond at temperatures ranging between 90K and 670K. The resonant nuclear reaction 13C(p,γ)14N was used to determine the depth distribution of the implanted 13C atoms. Variations in the depth profiles reflected changes in the mobility and recombination of the defects as a function of temperature. All of the depth profiles implanted at temperatures greater than ambient temperature displayed a bimodel distribution consisting of the expected internal peak, and an overlapping surface peak. This result is in contrast to previously obtained 19F depth-profiling results where all of the implanted fluorine moved to the surface when the substrate temperature was high enough; an indication of the importance of the role of chemical effects in determining the final resting positions of implanted ions. Annealing measurements indicated that the damaged area in the sub-ambient implants may consist of two regions each with its own dominant type of defect: a surface region extending to approximately 0.25 micrometers containing mobile single defects, and a sub-surface region extending to the end of the tail containing a more stable type of extended defect. Channelling measurements with 1.0 MeV protons corroborated all these results, and in addition indicated that the damaged region had attracted hydrogen from the interior which had presumably 'tied-off' all the dangling bonds in this area. The channelling measurements also suggest the occupation of specific lattice sites by the carbon self-interstitials. More measurements are needed to clarify what sites are occupied. Previously reported studies on 19F, have shown it to occupy two distinct lattice sites. A brief study was also carried out on the annealing characteristics of boron implanted into diamond at 90K; and on the implant temperature depth-dependence of lithium in the temperature range 90K - 670K. The nitrogen content of some amorphous hydrogenated carbon films was determined by profiling the 15N component using the 898 keV 15N(p,αγ)12C reaction. 41 figs., 5 tabs., 41 refs