| Summary: | The goal of this research work was to establish the Ionised Magnetron Sputter Deposition (IMSD) system and apply it to thin film fabrication. Using magnetron sputter deposition, with an additional built-in rf coil generating a rf coupled plasma to ionise sputtered atoms, the process provides a high level of control over the energy input to a growing film. The controllable parameters include ion flux, ion incident energy and the ratio of ions to neutrals of the depositing species. The possibility of depositing films and coatings with up to 85% of the depositing species as ions with energies controllable up to 150 eV offers a remarkable opportunity to engineer film growth and modify film properties by precisely controlled ion bombardment. The work presented here is concerned with the investigation and understanding of the basic properties of the IMSD process. It is composed of (1) a background introduction; (2) IMSD system characterisation; (3) characterisation of IMSD deposited metal thin films. Firstly, an introduction to magnetron sputtering and the effects of energetic bombardment on film properties, and a brief survey of ion assisted techniques are presented. The recently developed IMSD process is then introduced. The rf inductively coupled (RFI) plasma generated in the IMSD process was characterised using a single electrical probe. The RFI plasma is confined close to the substrate, and the bombarding ions are drawn directly from it, so that the plasma parameters are crucial to the ion bombardment on the substrate surface, in terms of ion flux and ion energy. It is found that the ion flux can be controlled by the power applied to the rf coil, which controls the ion density. The ion incident energy can be determined by the difference between plasma and substrate potentials. The ionisation fraction of the depositing flux (ratio of ions to total depositing atoms) has been measured by a parallel-plates method, which was developed here. The probe method was also employed later to confirm the measurement. Directionality of depositing flux was examined by depositing films into sub-micron vias and trenches.
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