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Energy dissipation through physical downscaling towards more complex types of memory and logic devices, loss of ultrapure water and consumption of large amounts of (toxic) chemicals for wafer cleaning processes, as well as high thermal budget of solid-state synthesis and thin film growth of standard semiconductors including the use of rare earth elements – all this poses great challenges for semiconductor materials science and technology. Therefore, research and development of alternative methods for micro- and nanofabrication and chemical functionalization of a new type of resource- and energy-efficient semiconductors as the core component of every computer chip is crucial. One of the promising opportunities is the transformation of today's complementary metal-oxide-semiconductor (CMOS) electronics into ecofriendly and neuroinspired electronics driven by molecular design and multi-level switching mechanisms at room temperature. The sustainable chemical technology of electron transport and switching materials in semiconductor manufacturing and the development of devices with new unconventional nanophysics, improved performance, and augmented functionalities (beyond-CMOS and More-than-Moore) is becoming increasingly important in the context of a gradual transition to a future-oriented concept of Internet of Everything (IoE). In this article, we focus on the technological significance of semiconductor preparation from single-source (molecular) precursors and the prospect of functionalizing semiconductors using DNA origami nanotechnology and stimuli-responsive metal–oxygen cluster ions such as polyoxometalates (POMs). We also describe the advanced characterization of these qualified molecular systems by soft X-rays. We emphasize the technical relevance of using solution-based methods for the bottom-up preparation of novel and hybrid semiconductors as well as their challenging scalability and the compatibility of methods of molecular technology with lithography-based mass production. Our article aims to contribute to the achievement of the United Nations' Sustainable Development Goal 9 (Industry, Innovation and Infrastructure). [ABSTRACT FROM AUTHOR]

This paper focuses on the development of electroplating on 150 mm wafer level for microsystem technology applications from 1-Ethyl-3-methylimidazolium chloride (EMImCl) with Aluminumtrichloride (AlCl3). The deposition was carried out on 150 mm wafers with Au or Al seed layers deposited by physical vapor deposition (PVD). The electrodeposition was carried out using pattern plating. On the Au seed layer, bipolar pulse plating was applied. Compared to the Au seed layer, the electrodeposition on the Al seed layer was favorable, with lower current densities and pulsing frequencies. Utilizing the recurrent galvanic pulses and avoiding ionic liquid convection, inhomogeneities lower than 15% were achieved with a laboratory plating cell. One major aspect of this study was the removal of the native Al oxide prior to deposition. It was investigated on the chip and wafer levels using either current- or potential-controlled removal pulses. This process step was affected by the plasma treatment of the wafer, thus the surface free energy, prior to plating. It turned out that a higher surface free energy hindered proper oxide removal at a potential of 3 V. The theory of oxide breakdown based on electrostriction force via the electrical field was applied to discuss the findings and to derive conclusions for future plating experiments. [ABSTRACT FROM AUTHOR]

The interaction of thin evaporating fluid films with solids is studied using the example of water on LiTaO3 (LTO). Adsorption energies are computed by ab initio density functional theory (DFT) and used to calculate the Gibbs free energy of adsorption of water on LTO. Integrating the disjoining pressure, consisting of molecular and structural components, with respect to film thickness gives an expression for the Gibbs free energy. In this way, parameters for the disjoining pressure can be calculated by fitting its integral to the Gibbs free energy computed by ab initio DFT. A combination of literature-known models for spin drying and evaporation is utilized to describe the temporal evolution of the water layer. The vapor above the water layer is modeled by diffusion and a mass balance is applied at the water–air interface. For thick initial layers, an analytical approximation is derived which only depends on fluid and ambient conditions but not on the substrate properties. [ABSTRACT FROM AUTHOR]

We report unipolar resistive switching in polycrystalline, hexagonal yttrium manganite thin films grown on unpatterned Pt metal coated SiO2/Si substrates with circular Al top electrodes. Electroforming-free or electroforming-based resistive switching is observed, depending on the chemical composition (Y1Mn1O3, Y0.95Mn1.05O3, Y1Mn0.99Ti0.01O3, and Y0.94Mn1.05Ti0.01O3). The number of loading cycles measured at room temperature for samples with Y1Mn1O3 and Y0.95Mn1.05O3 composition is larger than 103. The dominant conduction mechanism of the metal–insulator–metal structures between 295 K and 373 K in the high resistance state is space charge limited conduction and in the low resistance state is ohmic conduction. Activation energies in Ohm's law region in the high resistance state are calculated from the Arrhenius equation and are evaluated to be 0.39 ± 0.01 eV (Y1Mn1O3), 0.43 ± 0.01 eV (Y0.95Mn1.05O3), 0.34 ± 0.01 eV (Y1Mn0.99Ti0.01O3), and 0.38 ± 0.02 eV (Y0.94Mn1.05Ti0.01O3). [ABSTRACT FROM AUTHOR]

Polycrystalline YMnO3 thin films sandwiched between an un-patterned bottom electrode (Pt or Pt/Ti) and a circular top electrode (Au or Al) reveal an electroforming-free, unipolar resistive switching. We report YMnO3 resistive switching devices endurance depending on the bottom electrode and the top electrode. The number of loading cycles of the Al/YMnO3/Pt resistive switch is larger than 103. The resistance ratio between the high resistance (OFF) and the low resistance (ON) state is larger than 104, which can be further increased to 105 by decreasing the diameter of the Al top electrode. [ABSTRACT FROM AUTHOR]