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Scanning probe microscopy techniques and, in particular, scanning spreading resistance microscopy (SSRM) were used for a detailed characterization of focused ion beam (FIB) induced damage in the surrounding of purposely irradiated areas on silicon. It is shown that the damaged area detected using these techniques extends up to several micrometers around the irradiated structures. The influence of the key FIB processing parameters on the FIB induced damage was examined. Parameters which were taken into account are the ion dose (from 1012 to 1018 cm−2), the milled structure size (circle diameters from 0.25 to 10 µm), the beam energy (from 10 to 30 keV), and the beam current (from 1.5 to 280 pA). Moreover, the influence of the SSRM settings on the measurement results was investigate d. Settings which were considered are the bias voltage and the force applied to the tip during the SSRM analysis. High resolution transmission electron microscopy and secondary ion mass spectroscopy analyses were performed to validate the SSRM results. Scattering between Ga ions and residual gas particles in the vacuum chamber of the FIB tool is identified as the main reason for the observed damaged area.

Imprint specific process parameters like the residual layer thickness and the etch resistance of the UV polymers for the substrate etch process have to be optimized to introduce UV nanoimprint lithography (UV NIL) as a high-resolution, low-cost patterning technique for research and industry into electron device manufacturing. Additionally, UV NIL processes have to be compatible with conventional silicon (Si) semiconductor processing. Within this work, the minimization of the residual layer thickness by using a multi-drop ink-jet system, which was integrated into the imprint stepper NPS300 from S-E-T-(formerly SUSS MicroTec), in combination with a low viscous UV polymer from Asahi Glass Company is shown. The etch resistance of different UV polymers against the poly-Si etch process was increased by 50% with an appropriate post-exposure bake. A poly-Si dry etch process was used to pattern the gates of short channel MOSFETs. After optimizing the poly-Si etch, properly working short channel MOSFETs with a minimum gate length of about 90nm were fabricated demonstrating successfully the compatibility of UV NIL with conventional Si semiconductor processing on nanosized scale.

Scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM) were used to analyze focused ion beam (FIB) induced lateral damage around milled structures on silicon. For this purpose, circular shaped structures were realized, and the influence of the implanted Ga dose (ranging from 10^1^5 to 10^1^7cm^-^2) and of the patterned area dimension (diameters ranging from 1 to [email protected]) on the damage were examined. It is shown that the extension of the lateral damage around FIB milled structures is much larger than the area of the purposely irradiated regions (up to a factor of 5) and increases with both, Ga dose and pattern diameter. Besides, the unique capability of SCM and SSRM techniques for the detection of FIB induced damage is demonstrated. In particular, it is shown that their high sensitivity to low densities of defects allows detecting larger damaged areas compared to Atomic Force Microscopy (AFM) topography maps.

Recent improvements in the fabrication of integrated field emitters with a control electrode into scanning probe microscopy sensors are presented and discussed. Compared to earlier work the precursor material for the electron beam induced deposition of the emitter was changed from a Pt precursor ((CH3C5H4)Pt(CH3)3) to a C precursor (C14H10) which leads to a higher process yield and an improved process stability. The change of the material for the control electrode from Pt to Cr results in better compatibility to standard semiconductor processing. The field emitter devices were fabricated by focused charged particle beam processing revealing emission currents of 0.8µA/tip for gate voltages of about 65V. Possible reasons for the high turn-on voltages Vto were investigated by high resolution transmission electron microscopy combined with EDX analyses and approaches for reducing Vto are presented.

In this work, methods for an accurate extraction of parameters for the simulation of nanoscaled structuring by focused ion beams will be discussed. For this purpose the quantitative understanding of the underlying effects (i.e. redeposition of sputtered atoms, the dependence of sputter yield on the angle of incidence, and the influence of scattered ions) is obligatory. Parameter values obtained from experiment and simulation will be compared and successfully be applied for the simulation of sputtered 2D structures.