By using a Ga FIB system to spatially control the implantation of Ga into SiO(2) followed by vacuum annealing, we have fabricated self-assembled surface Ga nanodots with a high degree of control of nucleation location. The morphology of the Ga nanodots is closely related to Ga dose, showing a critical dose needed for nucleation that results in Ga nanodot formation just below the surface, while at higher doses Ga nanodots form on the surface as metallic Ga droplets. Possible applications include defining nucleation sites for subsequent growth, use as Ga source for GaN or GaAs quantum dots, or as catalyst for nanowire growth.

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In surface analysis such as AES (Auger electron spectroscopy) or XPS (x-ray photoelectron spectroscopy), ion sputtering is generally used in order to remove contaminated layers and to perform an in-depth profiling. It is important to align an ion beam at an analysis area and to estimate sputtering rates prior to an actual measurement. In this report, two methods are introduced how to align the ion beam. (a) Faraday cup method is applicable to quantitatively estimate the ion beam by monitoring current and (b) SiO 2 method is an easy way to visually align the ion beam position. Detailed alignment procedures are promised to be useful for daily analysis workers.

Three dimensional Auger elemental distributions have been constructed from the combination of high spatial resolution, two dimensional Auger maps obtained at multiple sputter depths. These three dimensional elemental distributions have been used to compare the interfacial regions for two kinds of silicon on insulator wafers. It is clearly seen that silicon oxide is formed as an island structure for the SIMOX specimen, whereas the UNIBOND specimen has a featureless structure at the Si∕SiO2 interface. Linear least squares fitting from several two dimensional maps obtained at different energies have been used to produce energy dispersive spectra from specific regions of high spatial resolution Auger maps. This technique was used to examine the interface region exposed from sputter craters through a silicon dioxide layer on a silicon substrate and through a Ni silicide film on a silicon substrate. The Si LVV spectra for the elemental silicon, oxide, and silicide components extracted from the multiple energy two dimensional maps can be used to map the chemical components in the interfacial regions.