Etching and passivation of Group IV semiconductors: Ge and SiGe

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High-areal capacity Si architecture as an on-chip anode for lithium-ion batteries

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Wet Chemical Processing of Ge in Acidic H(2)O(2)Solution: Nanoscale Etching and Surface Chemistry

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Photoanodic pyramid texturization of n-Ge(100) in HCl solution: unexpected anisotropy in the surface chemistry of etching

© 2019 The Royal Society of Chemistry. The process of electrochemical etching of n-Ge(100) surfaces was studied for aqueous HCl solutions by voltammetry, atomic force and scanning electron microscopy, reflectance measurements and X-ray photoelectron spectroscopy. Under applied potential conditions, unexpected random pyramid texturization was observed for the high HCl concentration range evidenced by the formation of characteristic (111) facets. The morphological changes were accompanied by a photocurrent enhancement and a decreased reflectance. By patterning the pyramids, a high structure density could be achieved. The resulting decrease of the reflectance indicates that the coupling of light into the semiconductor was improved. Integrated electrochemical X-ray photoelectron spectroscopy measurements allowed us to relate surface chlorination to the obtained morphological features. Photoanodic etching schemes are presented to provide insight into these striking results.status: publishe

Controlled Electrochemical Etching of Nanoporous Si Anodes and Its Discharge Behavior in Alkaline Si<i>–</i>Air Batteries

We report the fabrication of nanoporous silicon (nPSi) electrodes via electrochemical etching to form a porous Si layer with controllable thickness and pore size. Varying the etching time and ethanolic HF concentration results in different surface morphologies, with various degrees of electrolyte access depending on the pore characteristics. Optimizing the etching condition leads to well-developed nPSi electrodes, which have thick porous layers and smaller pore diameter and exhibit improved discharge behavior as anodes in alkaline Si–air cells in contrast to flat Si anode. Although electrochemical etching is effective in improving the interfacial characteristics of Si in terms of high surface area, we observed that mild anodization occurs and produces an oxide overlayer. We then show that this oxide layer in nPSi anodes can be effectively removed to produce an nPSi anode with good discharge behavior in an actual alkaline Si–air cell. In the future, the combination of high surface area nPSi anodes with nonaqueous electrolytes (e.g., room-temperature ionic liquid electrolyte) to minimize the strong passivation behavior and self-discharge in Si could lead to Si–air cells with a stable voltage profile and high anode utilization

Synthesis of DNA-Mimic Polymers based on Polyepichrolohydrin with adenine Moieties and Properties, Structure, Biocompatibility

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Synthesis of Chemically and Thermally Advanced Nonvolatile Polyimide Memorys

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Polymers Bearing Zwitterionic Sulfobetaine Brushes: Correlation between Thin Film Morphology and Bacterial adherence Properties

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Atomic-scale investigations on the wet etching kinetics of GeversusSiGe in acidic H(2)O(2)solutions: a postoperandosynchrotron XPS analysis

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Programmable Volatile Memory Devices of Nitrogen-Linked Poly(2,7-carbazole)s : Polymer Devices and Analysis of Devices Structure Using X-Ray Reflectivity

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