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Nanofabrication of super-high-aspect-ratio structures in hydrogen silsesquioxane from direct-write e-beam lithography and hot development Influence of hydrogen silsesquioxane resist exposure temperature on ultrahigh resolution electron beam lithography J.The influence of the development process on the ultimate resolution of electron beam lithography using ultrathin HSQ layers was studied. Different developers, of different types and strengths, were used to develop lines exposed at a variety of doses. Optimum exposures could be found for lines of widths between 7 and 12 nm, at a pitch of 20 nm. Lines smaller than 5 nm could not be fabricated using any of these developers. Changing the development time had no influence on this result. Width versus dose curves are presented for all three developers and a 60 s development time. A scaling is presented to enable an easy calculation of the exposure latitude for each linewidth. Using 100 keV electron beam lithography, we achieved 6 nm isolated features in a 10 nm thick HSQ layer on a silicon substrate. We also showed that dense structures ͑5 nm wide at a pitch of 20 nm͒ could be obtained using a 1:5 developer solution of Microposit 351: H 2 O.

We report on the epitaxial growth and the characterization of thin FePt films and the subsequent patterning of magnetic lattice structures. These structures can be used to trap ultracold atoms for quantum simulation experiments. We use molecular beam epitaxy to deposit monocrystalline FePt films with a thickness of 50 nm. The films are characterized with X-ray scattering and M€ ossbauer spectroscopy to determine the long range order parameter and the hard magnetic axes. A high monocrystalline fraction was measured as well as a strong remanent magnetization of M ¼ 900 kA/m and coercivity of 0.4 T. Using electron beam lithography and argon ion milling, we create lattice patterns with a period down to 200 nm, and a resolution of 30 nm. The resulting lattices are imaged in a scanning electron microscope in the cross-section created by a focused ion beam. A lattice with continuously varying lattice constant ranging from 5 lm down to 250 nm has been created to show the wide range of length scales that can now be created with this technique.

Abstract. Isolated dots and lines with 6 nm width are written in 20-nm-thick hydrogen silsesquioxane ͑HSQ͒ layers on silicon substrates, using 100-keV electron beam lithography. The main factors that might limit the resolution, i.e., beam size, writing strategy, resist material, electron dose, and development process, are discussed. We demonstrate that, by adjusting the development process, a very high resolution can be obtained. We report the achievement of 7 nm lines at a 20-nm pitch written in a 10-nm-thick HSQ layer, using a potassium-hydroxide ͑KOH͒-based developer instead of a classical tetra-methyl-ammonium hydroxide ͑TMAH͒ developer. This is the smallest pitch achieved to date using HSQ resist. We think that the resolution can be improved further, and is presently limited by either the beam diameter ͑which was not measured separately͒ or by the not-fully-optimized development process.

Isolated dots and lines with 6 nm width were written in 20 nm thick Hydrogen silsesquioxane (HSQ) layers on silicon substrates, using 100 keV electron beam lithography. The main factors that might limit the resolution, i.e. beam size, writing strategy, resist material, electron dose, development process, are discussed. We demonstrate that, by adjusting the development process, a very high resolution can be obtained. We report the achievement of 7 nm lines at a 20 nm pitch written in a 10 nm thick HSQ layer, using a KOH-based developer instead of a classical TMAH developer. This is the smallest pitch achieved to date using HSQ resist. We think that the resolution can be improved further, and is presently limited by either the beam diameter (which was not measured separately) or by the not fully optimized development process.