27 results
Search Results
Now showing 1 - 10 of 27
- ItemA Patternable and In Situ Formed Polymeric Zinc Blanket for a Reversible Zinc Anode in a Skin-Mountable Microbattery(Weinheim : Wiley-VCH, 2021) Zhu, Minshen; Hu, Junping; Lu, Qiongqiong; Dong, Haiyun; Karnaushenko, Dmitriy D.; Becker, Christian; Karnaushenko, Daniil; Li, Yang; Tang, Hongmei; Qu, Zhe; Ge, Jin; Schmidt, Oliver G.Owing to their high safety and reversibility, aqueous microbatteries using zinc anodes and an acid electrolyte have emerged as promising candidates for wearable electronics. However, a critical limitation that prevents implementing zinc chemistry at the microscale lies in its spontaneous corrosion in an acidic electrolyte that causes a capacity loss of 40% after a ten-hour rest. Widespread anti-corrosion techniques, such as polymer coating, often retard the kinetics of zinc plating/stripping and lack spatial control at the microscale. Here, a polyimide coating that resolves this dilemma is reported. The coating prevents corrosion and hence reduces the capacity loss of a standby microbattery to 10%. The coordination of carbonyl oxygen in the polyimide with zinc ions builds up over cycling, creating a zinc blanket that minimizes the concentration gradient through the electrode/electrolyte interface and thus allows for fast kinetics and low plating/stripping overpotential. The polyimide's patternable feature energizes microbatteries in both aqueous and hydrogel electrolytes, delivering a supercapacitor-level rate performance and 400 stable cycles in the hydrogel electrolyte. Moreover, the microbattery is able to be attached to human skin and offers strong resistance to deformations, splashing, and external shock. The skin-mountable microbattery demonstrates an excellent combination of anti-corrosion, reversibility, and durability in wearables. © 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH
- ItemDigital Electrochemistry for On-Chip Heterogeneous Material Integration(Weinheim : Wiley-VCH, 2021) Bao, Bin; Rivkin, Boris; Akbar, Farzin; Karnaushenko, Dmitriy D.; Bandari, Vineeth Kumar; Teuerle, Laura; Becker, Christian; Baunack, Stefan; Karnaushenko, Daniil; Schmidt, Oliver G.Many modern electronic applications rely on functional units arranged in an active-matrix integrated on a single chip. The active-matrix allows numerous identical device pixels to be addressed within a single system. However, next-generation electronics requires heterogeneous integration of dissimilar devices, where sensors, actuators, and display pixels sense and interact with the local environment. Heterogeneous material integration allows the reduction of size, increase of functionality, and enhancement of performance; however, it is challenging since front-end fabrication technologies in microelectronics put extremely high demands on materials, fabrication protocols, and processing environments. To overcome the obstacle in heterogeneous material integration, digital electrochemistry is explored here, which site-selectively carries out electrochemical processes to deposit and address electroactive materials within the pixel array. More specifically, an amorphous indium-gallium-zinc oxide (a-IGZO) thin-film-transistor (TFT) active-matrix is used to address pixels within the matrix and locally control electrochemical reactions for material growth and actuation. The digital electrochemistry procedure is studied in-depth by using polypyrrole (PPy) as a model material. Active-matrix-driven multicolored electrochromic patterns and actuator arrays are fabricated to demonstrate the capabilities of this approach for material integration. The approach can be extended to a broad range of materials and structures, opening up a new path for advanced heterogeneous microsystem integration.
- ItemDirect transfer of magnetic sensor devices to elastomeric supports for stretchable electronics(Hoboken, NJ : Wiley, 2015) Melzer, Michael; Karnaushenko, Daniil; Lin, Gungun; Baunack, Stefan; Makarov, Denys; Schmidt, Oliver G.A novel fabrication method for stretchable magnetoresistive sensors is introduced, which allows the transfer of a complex microsensor systems prepared on common rigid donor substrates to prestretched elastomeric membranes in a single step. This direct transfer printing method boosts the fabrication potential of stretchable magnetoelectronics in terms of miniaturization and level of complexity, and provides strain‐invariant sensors up to 30% tensile deformation.
- ItemWearable magnetic field sensors for flexible electronics(Hoboken, NJ : Wiley, 2014) Melzer, Michael; Mönch, Jens Ingolf; Makarov, Denys; Zabila, Yevhen; Bermúdez, Gilbert Santiago Cañón; Karnaushenko, Daniil; Baunack, Stefan; Bahr, Falk; Yan, Chenglin; Kaltenbrunner, Martin; Schmidt, Oliver G.Highly flexible bismuth Hall sensors on polymeric foils are fabricated, and the key optimization steps that are required to boost their sensitivity to the bulk value are identified. The sensor can be bent around the wrist or positioned on the finger to realize an interactive pointing device for wearable electronics. Furthermore, this technology is of great interest for the rapidly developing market of eMobility, for optimization of eMotors and magnetic bearings.
- ItemActive Matrix Flexible Sensory Systems: Materials, Design, Fabrication, and Integration(Weinheim : Wiley-VCH Verlag GmbH & Co. KGaA, 2022) Bao, Bin; Karnaushenko, Dmitriy D.; Schmidt, Oliver G.; Song, Yanlin; Karnaushenko, DaniilA variety of modern applications including soft robotics, prosthetics, and health monitoring devices that cover electronic skins (e-skins), wearables as well as implants have been developed within the last two decades to bridge the gap between artificial and biological systems. During this development, high-density integration of various sensing modalities into flexible electronic devices becomes vitally important to improve the perception and interaction of the human bodies and robotic appliances with external environment. As a key component in flexible electronics, the flexible thin-film transistors (TFTs) have seen significant advances, allowing for building flexible active matrices. The flexible active matrices have been integrated with distributed arrays of sensing elements, enabling the detection of signals over a large area. The integration of sensors within pixels of flexible active matrices has brought the application scenarios to a higher level of sophistication with many advanced functionalities. Herein, recent progress in the active matrix flexible sensory systems is reviewed. The materials used to construct the semiconductor channels, the dielectric layers, and the flexible substrates for the active matrices are summarized. The pixel designs and fabrication strategies for the active matrix flexible sensory systems are briefly discussed. The applications of the flexible sensory systems are exemplified by reviewing pressure sensors, temperature sensors, photodetectors, magnetic sensors, and biosignal sensors. At the end, the recent development is summarized and the vision on the further advances of flexible active matrix sensory systems is provided.
- ItemBiomimetic microelectronics for regenerative neuronal cuff implants(Hoboken, NJ : Wiley, 2015) Karnaushenko, Daniil; Münzenrieder, Niko; Karnaushenko, Dmitriy D.; Koch, Britta; Meyer, Anne K.; Baunack, Stefan; Petti, Luisa; Tröster, Gerhard; Makarov, Denys; Schmidt, Oliver G.Smart biomimetics, a unique class of devices combining the mechanical adaptivity of soft actuators with the imperceptibility of microelectronics, is introduced. Due to their inherent ability to self‐assemble, biomimetic microelectronics can firmly yet gently attach to an inorganic or biological tissue enabling enclosure of, for example, nervous fibers, or guide the growth of neuronal cells during regeneration.
- ItemMechanical Characterization of Compact Rolled-up Microtubes Using In Situ Scanning Electron Microscopy Nanoindentation and Finite Element Analysis(Weinheim : Wiley-VCH, 2021) Moradi, Somayeh; Jöhrmann, Nathanael; Karnaushenko, Dmitriy D.; Zschenderlein, Uwe; Karnaushenko, Daniil; Wunderle, Bernhard; Schmidt, Oliver G.Self-assembled Swiss-roll microstructures (SRMs) are widely explored to build up microelectronic devices such as capacitors, transistors, or inductors as well as sensors and lab-in-a-tube systems. These devices often need to be transferred to a special position on a microchip or printed circuit board for the final application. Such a device transfer is typically conducted by a pick-and-place process exerting enormous mechanical loads onto the 3D components that may cause catastrophic failure of the device. Herein, the mechanical deformation behavior of SRMs using experiments and simulations is investigated. SRMs using in situ scanning electron microscopy (SEM) combined with nanoindentation are characterized. This allows us to mimic and characterize mechanical loads as they occur in a pick-and-place process. The deformation response of SRMs depends on three geometrical factors, i.e., the number of windings, compactness of consecutive windings, and inner diameter of the microtube. Nonlinear finite element analysis (FEA) showing good agreement with experiments is performed. It is believed that the insights into the mechanical loading of 3D self-assembled architectures will lead to novel techniques suitable for a new generation of pick-and-place machines operating at the microscale. © 2021 The Authors. Advanced Engineering Materials published by Wiley-VCH GmbH
- ItemSelf-assembly of Co/Pt stripes with current-induced domain wall motion towards 3D racetrack devices([London] : Nature Publishing Group UK, 2024) Fedorov, Pavel; Soldatov, Ivan; Neu, Volker; Schäfer, Rudolf; Schmidt, Oliver G.; Karnaushenko, DaniilModification of the magnetic properties under the induced strain and curvature is a promising avenue to build three-dimensional magnetic devices, based on the domain wall motion. So far, most of the studies with 3D magnetic structures were performed in the helixes and nanowires, mainly with stationary domain walls. In this study, we demonstrate the impact of 3D geometry, strain and curvature on the current-induced domain wall motion and spin-orbital torque efficiency in the heterostructure, realized via a self-assembly rolling technique on a polymeric platform. We introduce a complete 3D memory unit with write, read and store functionality, all based on the field-free domain wall motion. Additionally, we conducted a comparative analysis between 2D and 3D structures, particularly addressing the influence of heat during the electric current pulse sequences. Finally, we demonstrated a remarkable increase of 30% in spin-torque efficiency in 3D configuration.
- ItemA new dimension for magnetosensitive e-skins: active matrix integrated micro-origami sensor arrays([London] : Nature Publishing Group UK, 2022) Becker, Christian; Bao, Bin; Karnaushenko, Dmitriy D.; Bandari, Vineeth Kumar; Rivkin, Boris; Li, Zhe; Faghih, Maryam; Karnaushenko, Daniil; Schmidt, Oliver G.Magnetic sensors are widely used in our daily life for assessing the position and orientation of objects. Recently, the magnetic sensing modality has been introduced to electronic skins (e-skins), enabling remote perception of moving objects. However, the integration density of magnetic sensors is limited and the vector properties of the magnetic field cannot be fully explored since the sensors can only perceive field components in one or two dimensions. Here, we report an approach to fabricate high-density integrated active matrix magnetic sensor with three-dimensional (3D) magnetic vector field sensing capability. The 3D magnetic sensor is composed of an array of self-assembled micro-origami cubic architectures with biased anisotropic magnetoresistance (AMR) sensors manufactured in a wafer-scale process. Integrating the 3D magnetic sensors into an e-skin with embedded magnetic hairs enables real-time multidirectional tactile perception. We demonstrate a versatile approach for the fabrication of active matrix integrated 3D sensor arrays using micro-origami and pave the way for new electronic devices relying on the autonomous rearrangement of functional elements in space.
- ItemImperceptible magnetoelectronics(London : Nature Publishing Group, 2015) Melzer, Michael; Kaltenbrunner, Martin; Makarov, Denys; Karnaushenko, Dmitriy; Karnaushenko, Daniil; Sekitani, Tsuyoshi; Someya, Takao; Schmidt, Oliver G.Future electronic skin aims to mimic nature’s original both in functionality and appearance. Although some of the multifaceted properties of human skin may remain exclusive to the biological system, electronics opens a unique path that leads beyond imitation and could equip us with unfamiliar senses. Here we demonstrate giant magnetoresistive sensor foils with high sensitivity, unmatched flexibility and mechanical endurance. They are <2 μm thick, extremely flexible (bending radii <3 μm), lightweight (≈3 g m−2) and wearable as imperceptible magneto-sensitive skin that enables proximity detection, navigation and touchless control. On elastomeric supports, they can be stretched uniaxially or biaxially, reaching strains of >270% and endure over 1,000 cycles without fatigue. These ultrathin magnetic field sensors readily conform to ubiquitous objects including human skin and offer a new sense for soft robotics, safety and healthcare monitoring, consumer electronics and electronic skin devices.
- «
- 1 (current)
- 2
- 3
- »