Aspects of electron microscopic characterization of thin solid films

Various aspects of the electron microscopic characterisation of thin solid films are investigated, viz. the determination of the thickness and the microstructure of thin solid films. Some effects of various deposition methods and conditions on microstructure were investigated. A certain amount of background study was performed into various deposition methods. All of the investigations were performed using either Ni or Si films or a combination of the two. Thin films were prepared in four basic ways, viz. vacuum deposition, sputter deposition, electroless plating and chemical jet thinning. The electroless plating was done in a commercial, low phosphorus content, Ni-P plating solution. Three different thickness determination methods were performed on thin films, in order to produce film thickness standards. The standardisation thickness determination methods were: 1. Mass determination, where a Ni film was deposited onto a 100 cm2 foil, and the resultant mass increase was determined by means of accurate weighing and converted to a thickness value. 2. A commercial oscillating piezo-electric crystal thickness monitor. 3. Rutherford backscattering of 2000 keV alpha particles. Here, the thicknesses were determined in three different ways, viz. the width of the energy peak of alphas backscattered off the Ni film, the shift in energy of the alphas backscattered off the Si substrate, and integral count of alphas backscattered off Ni. The thickness determination methods calibrated using these standardised specimens were: 1) Electron transmission through a thin film. 2) A plot of incident electron energy versus x-ray intensity. 3) A method based on the energy at which the substrate x-rays are first detected and 4) a method based on x-ray spectrometry. Thin film microstructure in imaging and selected area diffraction modes was determined. Sputter deposited Ni films were also studied