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On-chip integration of solid-state thin-film lithium-ion batteries (LIBs) can be a feasible solution for integrating energy storage devices directly into microchips. Constituting an energy source in such devices requires an implementation of the battery on a silicon substrate and prevent lithium ions diffusing from the active battery materials into other components. In this paper, we compare 10 nm titanium nitride, deposited with two techniques: thermal atomic layer deposition (ALD) and pulsed chemical vapor deposition (pCVD). TiN films feasibility as a barrier layer is investigated before and after electrochemical cycling by time of flight secondary ion mass spectrometry and x-ray photoelectron spectroscopy. The results show the superior performance of the TiN prepared with ALD in comparison to pCVD. This drawback of pCVD identify the dependency of TiN stability on the composition ratio between nitrogen and oxygen, and the co-existence of surface/interface impurities. Moreover, 35 nm films prepared with pCVD compared with 10 nm films to show the effectiveness of increasing the thickness. Finally, we show that the concentration of oxygen atoms at grain boundaries can be a leading cause of TiN abruption. For the pCVD sample, this can be related to the higher number of crystal defects in comparison to ALD.

For the analysis of thin films, with high aspect ratio (HAR) structures, time-of-flight secondary ion mass spectrometry (ToF-SIMS) overcomes several challenges in comparison to other frequently used techniques such as electron microscopy. The research presented herein focuses on two different kinds of HAR structures that represent different semiconductor technologies. In the first study, ToF-SIMS is used to illustrate cobalt seed layer corrosion by the copper electrolyte within the large through-silicon-vias (TSVs) before and after copper electroplating. However, due to the sample&rsquo, s surface topography, ToF-SIMS analysis proved to be difficult due to the geometrical shadowing effects. Henceforth, in the second study, we introduce a new test platform to eliminate the difficulties with the HAR structures, and again, use ToF-SIMS for elemental analysis. We use data image slicing of 3D ToF-SIMS analysis combined with lateral HAR test chips (PillarHall&trade, ) to study the uniformity of silicon dopant concentration in atomic layer deposited (ALD) HfO2 thin films.

Doped-HfO2 based ferroelectrics have been widely studied for the application in advanced CMOS technologies such as ferroelectric random-access memory (FeRAM) or ferroelectric field effect transistor (FeFET). Studies show that there is a strong link between the ferroelectric properties with the highest remanent polarization value of the doped-HfO2 and the structural properties of the film. In ultrathin ferroelectric films, the concentration of La dopant directly affects the stabilization of the polar orthorhombic phase (Pca2I) which impact spontaneous polarization of ferroelectric films[1]. In this research, we characterized La concentration in HfO2 on 3D structures to show the uniformity of dopant distribution inside the hafnia from top to bottom of a high aspect ratio (HAR) structure. We use atomic layer deposition (ALD) for excellent step coverage in HAR structures. ALD provides precise controlling of the dopant distribution within a layer. However, regulating the dopant concentration in a thin film requires a platform which could be easily characterized and measured. In this study, we used lateral high aspect ratio (LHAR) test structures (PillarHall™ developed at VTT [2-3]) as a new platform to perform precise measurements of hafnia doped thin film along the deposition gap in LHAR structure. On this purpose, we combined time-of-flight secondary ion mass spectrometry (ToF-SIMS) with X-ray photoelectron spectroscopy (XPS) and highly novel hard-XPS (HAXPES) to make a comparative study on deposited La-doped HfO2 thin films with ALD. We compare La stoichiometry in planar structures with LHAR structures. By then with ToF-SIMS capability of data imaging and integrating data points from the region of interest, doping profiles can be quantified together with understanding the trench wall in-depth penetration. Furthermore, we compared generated quantitative information from depth analysis of different La concentrations in LHAR structures with the help of both traditional XPS measurements using an Al Kα X-ray source and extended depth of analysis experiments using a Cr Kα (hard) X-ray source (the Cr X-ray source provides depths analysis about 3 times higher than standard Al Kα source).References[1] Mart et al., Appl. Phys. Lett., 114, no. 10, 2019.[2] Gao et al., Vac. Sci. Technol. A, 33, 2015.[3] Puurunen et al., AF-SuA15, ALD 2017.

To identify optimal hydrogen production conditions using growing cultures of Rhodobacter sphaeroides DSM 158 the effects of varying the reactor’s volumetric power input (0.01–1.4 kW m −3 ) and irradiation intensity (5–2500 W m −2 ) were investigated in batch and continuous production modes. Irradiation intensity had a greater effect on hydrogen production than volumetric power input. Hydrogen production and photofermentative biomass formation were maximized by irradiation at 2250 W m −2 with a volumetric power input of 0.55 kW m −3 . The bacterial dry weight (2.64 g L −1 ) and rate of hydrogen production (195 mL L −1 h −1 ) achieved under these conditions were greater than any that have previously been reported for batch-mode hydrogen production by R. sphaeroides . Continuous mode experiments ( D = 0.1 h −1 ) yielded a bacterial dry weight, hydrogen production rate, productivity and hydrogen yield of 2.35 ± 0.18 g L −1 , 165 ± 6.2 mL L −1 h −1 , 3.96 L L −1 d −1 and 36.6%, respectively.

Microbiological photosynthesis is a promising tool for producing hydrogen in an ecologically friendly and economically efficient way. Certain microorganisms (e.g. algae and bacteria) can produce hydrogen using hydrogenase and/or nitrogenase enzymes. However, their natural capacity to produce hydrogen is relatively low. Thus, there is a need to optimize their core photosynthetic processes as well as their cultivation, for more efficient hydrogen production. This review aims to provide a holistic overview of the recent technological and research developments relating to photobiological hydrogen production and downstream processing. First we cover photobiological hydrogen synthesis within cells and the enzymes that catalyze the hydrogen production. This is followed by strategies for enhancing bacterial hydrogen production by genetic engineering, technological development, and innovation in bioreactor design. The remaining sections focus on hydrogen as a product, that is, quantification via (in-process) gas analysis, recent developments in gas separation technology. Finally, a discussion of the sociological (market) barriers to future hydrogen usage is provided as well as an overview of methods for life cycle assessment that can be used to calculate the environmental consequences of hydrogen production.

Herein, growth kinetics, crystal structure, and the uniformity of titanium oxide (TiO2) thin films prepared using atomic layer deposition (ALD) and plasma-enhanced ALD (PE-ALD) are studied. TiO2 thin films are grown using titanium tetrachloride (TiCl4), water, and oxygen precursors. Using ALD, TiO2 is grown in the temperature range of 270â310 °C thermally and in the range of 300â400 °C with PE-ALD. In spite of the plasma process yielding better uniformity on planar structures, the optimized thermal process provides a remarkable conformal step coverage within deep trenches. In addition, the change in the crystal structure and phase transitions of TiO2 is presented herein. This is attempted at using TiO2 as a component material to grow lithium titanate (LTO) as an electrode material in solid-state lithium-ion batteries (LIBs). Thereby, different substrates are used. In comparison to the silicon (Si) substrate, silicon oxide (SiO2) and titanium nitride (TiN) lead to crystal phase transformation while annealing. Measurements are performed using in situ high-temperature X-ray diffraction (HT-XRD). It is also shown that when TiN is sandwiched between TiO2 and the silicon substrate, the TiO2 thin film (25 nm) gradually changes from an anatase to a rutile structure.

Zusammenfassung Es werden die Ergebnisse zur Entwicklung von molekular basierten Prinzipien zur Detektion von Proteinen z.B. Virusproteinen dargestellt. Diese bestehen im Wesentlichen im Nachweis der spezifischen Interaktion der Aptamere mit Proteinen durch impedimetrische Messverfahren und der Oberflächenplasmonenresonanz-Spektroskopie. Zudem werden die rekombinante Expression des Kapsidproteins des Norovirus und dessen Verwendung zur Selektion Norovirus-spezifischer Aptamere beschrieben.

DNA nanostructures are promising construction materials to bridge the gap between self-assembly of functional molecules and conventional top-down fabrication methods in nanotechnology. Their positioning onto specific locations of a microstructured substrate is an important task towards this aim. Here we study manipulation and positioning of pristine and of gold nanoparticle-conjugated tubular DNA origami structures using ac dielectrophoresis. The dielectrophoretic behavior was investigated employing fluorescence microscopy. For the pristine origami, a significant dielectrophoretic response was found to take place in the megahertz range, whereas, due to the higher polarizability of the metallic nanoparticles, the nanoparticle/DNA hybrid structures required a lower electrical field strength and frequency for a comparable trapping at the edges of the electrode structure. The nanoparticle conjugation additionally resulted in a remarkable alteration of the DNA structure arrangement. The growth of linear, chain-like structures in between electrodes at applied frequencies in the megahertz range was observed. The long-range chain formation is caused by a local, gold nanoparticle-induced field concentration along the DNA nanostructures, which in turn, creates dielectrophoretic forces that enable the observed self-alignment of the hybrid structures.

An easily feasible, species-conserving and inexpensive protocol for the extraction of total arsenic and arsenic species from terrestrial plants was designed and applied to the investigation of accumulation and metabolization of arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA(V)), and dimethylarsinate (DMA(V)) by the model plant Tropaeolum majus. In contrast to existing extraction methods hazardous additives and elaborate procedures to enhance the extraction yields were omitted. The proposed protocol is suited to down-scale the sample sizes used for the extractions and to promote a compartmentally resolved analysis of the arsenic distribution within individual leaves, leaf stalks, and stems instead of the conventional extraction of pooled samples. In a two-step extraction, the high extraction efficiencies (85–92%) for arsenic achieved by phosphate buffer from larger amounts (200 mg) of homogenized leaf material in a one-step extraction, could be enhanced to 94–100% in a second extraction step. A strong dependence of the arsenic extractability on the type of arsenic species accumulated in the tissue as well as on the type of the tissue (leaf, leaf stalk, stem) was found. For the extraction of 5 mm long segments cut from individual leaves without previous homogenization of the plant parts yields between 75 and 93% depending on arsenic species prevailing in the cells were obtained using 1 or 10 mM phosphate buffer. The total extraction and analysis protocol was validated using a standard reference material as well as by spiking experiments. The arsenic species analysis by IC/ICPMS revealed a number of nine unidentified metabolites in the plant extracts in addition to the species MMA(V), DMA(V), As(III), and As(V) that were provided to the plants during their growth phase.