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FIB technologies possess a unique ability to form topographies that are difficult or impossible to generate with binary etching through typical photo-lithography. The ability to arbitrarily vary the spatial dose distribution and therefore the amount of milling opens possibilities for the production of a wide range of functional structures with applications in biology, chemistry, and optics. However in practice, the realization of these goals is made difficult by the angular dependence of the sputtering yield and redeposition effects that vary as the topography evolves. An inverse modeling algorithm that optimizes dose profiles, defined as the superposition of time invariant pixel dose profiles (determined from the beam parameters and pixel dwell times), is presented. The response of the target to a set of pixel dwell times in modeled by numerical continuum simulations utilizing 1st and 2nd order sputtering and redeposition, the resulting surfaces are evaluated with respect to a target topography in an error minimization routine. Two algorithms for the parameterization of pixel dwell times are presented, a direct pixel dwell time method, and an abstracted method that uses a refineable piecewise linear cage function to generate pixel dwell times from a minimal number of parameters. The cage function method demonstrates great flexibility and efficiency as compared to the direct fitting method with performance enhancements exceeding ∼10× as compared to direct fitting for medium to large simulation sets. Furthermore, the refineable nature of the cage function enables solutions to adapt to the desired target function. The optimization algorithm, although working with stationary dose profiles, is demonstrated to be applicable also outside the quasi-static approximation. Experimental data confirms the viability of the solutions for 5 × 7 μm deep lens like structures defined by 90 pixel dwell times.

In this article we explore the application of scanning capacitance microscopy (SCM) for studying focused ion beam (FIB) induced damage in silicon. We qualitatively determine the technologically important beam shape by measuring the SCM image of FIB processed implantation spots and by comparison of topographical and SCM data. Further, we investigate the question how deep impinging ions generate measurable damage below the silicon surface. For this purpose, trenches were manufactured using FIB and analyzed by SCM in cross-sectional geometry.

In this paper we explore the application of scanning capacitance microscopy (SCM) for studying focussed ion beam (FIB) induced damage in silicon. We qualitatively determine the technologically important beam shape by measuring the SCM image of FIB processed implantation spots, and by comparison of topographical and SCM data. Further, we investigate how deep impinging ions generate measurable damage below the silicon surface. For this purpose, trenches were manufactured using FIB and analysed by SCM in cross-sectional geometry.

This paper describes the results of the 3rd Europe-wide enquiry of the Working Party on Analytical Chemistry (WPAC) of the Federation of European Chemical Societies (FECS) in the field of education of analytical chemists at university level. While the first enquiry launched in 1983/84 showed the importance of separate chairs in Analytical Chemistry for maintaining the quality of modern curricula in a rapidly changing world and the evaluation of the second questionnaire from 1989/90 was the basis of the “WPAC-Eurocurriculum”, this third enquiry (1995) was aimed at determining the impact that the WPAC-Eurocurriculum initiative has made on the “Advanced Study Schemes” in Analytical Chemistry at European universities 3 years after its announcement. From the 141 questionnaires evaluated, it could be clearly shown that the WPAC-Eurocurriculum is already well known and accepted at universities in Europe, but not yet sufficiently established. Institutions having the WPAC-Eurocurriculum already implemented, however show a more flexible, modern and application oriented approach to the advanced study programme in Analytical Chemistry than universities teaching in the old way.

Using a generalized extraction method, the fixed charge density Nint at the interface between in situ deposited SiN and 5 nm thick AlGaN barrier is evaluated by measurements of threshold voltage Vth of an AlGaN/GaN metal insulator semiconductor high electron mobility transistor as a function of SiN thickness. The thickness of the originally deposited 50 nm thick SiN layer is reduced by dry etching. The extracted Nint is in the order of the AlGaN polarization charge density. The total removal of the in situ SiN cap leads to a complete depletion of the channel region resulting in Vth = +1 V. Fabrication of a gate stack with Al2O3 as a second cap layer, deposited on top of the in situ SiN, is not introducing additional fixed charges at the SiN/Al2O3 interface.