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Herein, a process for the large‐area passivating and contacting of nanowire‐based solar cells is demonstrated. The nanowire‐based solar cells are prepared on layered laser crystallization (LLC) polycrystalline silicon (pc‐Si) thin films with thickness less than 2 μm. It is demonstrated that the space between the nanowires can be filled with a passivating dielectrics Al2O3 layer, and the nanowire tips can be exposed by a self‐regulating selective etching of the Al2O3 deposited on the tips and that on the sidewalls. The exposed tips of the nanowires can be connected by a transparent conducting aluminum‐doped zinc oxide (Al:ZnO or AZO) layer deposited by atomic layer deposition (ALD). The laser beam‐induced current mapping (LBIC) demonstrates that the current density can increase up to 63% at 633 nm due to light trapping and the superior passivation of the nanowires with an thin pc‐Si film of only 1.73 μm. [ABSTRACT FROM AUTHOR]

In order to facilitate the design freedom for the implementation of textile-integrated electronics, we seek flexible transparent conductive electrodes (TCEs) that can withstand not only the mechanical stresses encountered during use but also the thermal stresses of post-treatment. The transparent conductive oxides (TCO) typically used for this purpose are rigid in comparison to the fibers or textiles they are intended to coat. In this paper, a TCO, specifically aluminum-doped zinc oxide (Al:ZnO), is combined with an underlying layer of silver nanowires (Ag-NW). This combination brings together the advantages of a closed, conductive Al:ZnO layer and a flexible Ag-NW layer, forming a TCE. The result is a transparency of 20–25% (within the 400–800 nm range) and a sheet resistance of 10 Ω/sq that remains almost unchanged, even after post-treatment at 180 °C. [ABSTRACT FROM AUTHOR]

We present the design considerations of an autonomous wireless sensor and discuss the fabrication and testing of the various components including the energy harvester, the active sensing devices and the power management and sensor interface circuits. A common materials platform, namely, nanowires, enables us to fabricate state-of-the-art components at reduced volume and show chemical sensing within the available energy budget. We demonstrate a photovoltaic mini-module made of silicon nanowire solar cells, each of 0.5 mm area, which delivers a power of 260 μW and an open circuit voltage of 2 V at one sun illumination. Using nanowire platforms two sensing applications are presented. Combining functionalised suspended Si nanowires with a novel microfluidic fluid delivery system, fully integrated microfluidic-sensor devices are examined as sensors for streptavidin and pH, whereas, using a microchip modified with Pd nanowires provides a power efficient and fast early hydrogen gas detection method. Finally, an ultra-low power, efficient solar energy harvesting and sensing microsystem augmented with a 6 mAh rechargeable battery allows for less than 20 μW power consumption and 425 h sensor operation even without energy harvesting. [ABSTRACT FROM AUTHOR]