At the onset of this study, the work presented in Chapter 3 of this thesis was theudprimary focus. The work was motivated by JF Prins where he observed the formationudof diamond layers on copper followed by C+ implantation into copper. This initialudresult suggested that it may be possible to generate single crystal diamond layers onudsingle crystal copper. Subsequent efforts to reproduce this result failed. A uniqueudend station was developed where a number of parameters could be altered duringudthe implantation process. A series of carbon ion implantations were carried out onudcopper and copper-nickel (FCC) single crystals in this end station. The layers wereudcharacterised using initially Auger Electron Spectroscopy (AES), Low Energy ElectronudDiffraction (LEED) and later Raman Spectroscopy. During the early period of thisudstudy, the surface science equipment at the then Wits-Schonland Research Instituteudfor Nuclear Sciences, was constantly giving problems. The time constraints on waitingudfor funds to be made available to repair the equipment, urged me to pursue alternativeudresearch endeavours and the results of this research is presented in chapter 4 and 5.udThe initial work will be investigated further in the future. Details of the end stationudare presented and the initial results of carbon layers generated in this end station areudpresented.udIn chapter 4, a study of C+ implantation into a type IIa (FCC single crystal) diamondudusing the cold implantation rapid annealing (CIRA) technique is reported. The Ramanudspectrum was recorded as a function of annealing temperature and C+ ion dose. De-udfect peaks at 1450, 1498 and 1638 cm−1 appear in the Raman spectra, which have beenudpreviously considered to be unique to MeV implantation. The maximum energy ofudimplantation used in this study was 170 keV. The peaks were monitored as a functionudof annealing temperature and ion dose. The annealing behaviour of the peaks wereudsimilar to those observed in the MeV implantation experiments. It is thus concludedudthat the defects that give rise to these peaks are related to the point-defect interac-udtions that occur within the implantation regime and not to the implantation energy.ud1udUnderstanding the nature of the defects that arise during the implantation annealingudprocess, allows one to manipulate the implantation-annealing cycle, so as to generateuddefect structures that are useful in the fabrication of an active device in a diamondudsubstrate. This is shown in chapter 5.udA p-type (type IIb, FCC crystal) diamond was implanted with either carbon or phos-udphorus ions using the cold implantation rapid annealing (CIRA) process. In each case,udthe energies and doses were chosen such that upon annealing, the implanted layerudwould act as an n-type electrode. The electroluminescence (EL) emitted from theseudcarbon and phosphorus junctions, when biased in the forward direction, was comparedudas functions of annealing and diode temperatures. Typical luminescence bands such asudthose observed in cathodoluminescence (CL), in particular blue band A (2.90 eV) andudgreen band (2.40 eV) were observed. Two bands centred around 2.06 and 4.0 eV wereudalso observed for both the carbon and phosphorus junctions, while a band at 4.45 eVudappeared only in the phosphorus implanted junction. This was the first time that theud4.45 eV band was observed in an electroluminescent junction.
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