Single-molecule force-spectroscopy methods such as magnetic and optical tweezers have emerged as powerful tools for the detailed study of biomechanical aspects of DNA-enzyme interactions. As typically only a single molecule of DNA is addressed in an individual experiment, these methods suffer from a low data throughput. Here, we report a novel method for targeted, nonrandom immobilization of DNA-tethered magnetic beads in regular arrays through microcontact printing of DNA end-binding labels. We show that the increase in density due to the arrangement of DNA-bead tethers in regular arrays can give rise to a one-order-of-magnitude improvement in data-throughput in magnetic tweezers experiments. We demonstrate the applicability of this technique in tweezers experiments where up to 450 beads are simultaneously tracked in parallel, yielding statistical data on the mechanics of DNA for 357 molecules from a single experimental run. Our technique paves the way for kilo-molecule force spectroscopy experiments, enabling the study of rare events in DNA-protein interactions and the acquisition of large statistical data sets from individual experimental runs.

For the introduction of EUV lithography, development of high performance EUV resists is of key importance. This development involves studies into resist sensitivity, resolving power and pattern uniformity. We have used a subnanometer-sized 30 keV helium ion beam to expose chemically amplified (CAR) EUV resists. There are similarities in the response of resists to He + ions and EUV photons: both excite Secondary Electrons with similar energy distributions. The weak backscattering of the He + ions results in ultra-low proximity effects. This fact enables the exposure of dense and detailed patterns by focused He + ion beams without the need for proximity correction. This paper presents contact holes and lines at 40-nm pitch in an EUV CAR resist. We have used resist sensitivity, contrast, resolution (CD) and pattern fidelity (LCDU, LWR and dose-to-print) as metrics for a comparison of SHIBL with EUVL. We show that Scanning Helium Ion Beam Lithography (SHIBL) can be a useful and economically attractive technology to (pre-)screen novel EUV resists prior to their final performance evaluation in an EUV scanner.

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Non-deterministic polynomial (NP-) complete problems, whose number of possible solutions grows exponentially with the number of variables, require by necessity massively parallel computation. Because sequential computers, such as solid state-based ones, can solve only small instances of these problems within a reasonable time frame, parallel computation using motile biological agents in nano- and micro-scale networks has been proposed as an alternative computational paradigm. Previous work demonstrated that protein molecular motors-driven cytoskeletal filaments are able to solve a small instance of an NP complete problem, i.e. the subset sum problem, embedded in a network. Autonomously moving bacteria are interesting alternatives to these motor driven filaments for solving such problems, because they are easier to operate with, and have the possible advantage of biological cell division. Before scaling up to large computational networks, bacterial motility behaviour in various geometrical structures has to be characterised, the stochastic traffic splitting in the junctions of computation devices has to be optimized, and the computational error rates have to be minimized. In this work, test structures and junctions have been designed, fabricated, tested, and optimized, leading to specific design rules and fabrication flowcharts, resulting in correctly functioning bio-computation networks.