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Synthetic melanin based metal–insulator–semiconductor devices are fabricated for the first time thanks to silicon surface wettability modification by using dielectric barrier discharge plasma. Ambipolar charge trapping in air and ion drift mechanisms under vacuum are identified by capacitance–voltage hysteresis loops. These results aim to foresee the possible integration of synthetic melanin layers as a novel capacitor in organic polymer based devices.

Shape similarity assessment is a fundamental geometric reasoning problem that finds application in several different product design and manufacturing applications. A computationally efficient way to assess shape similarity is to first abstract 3D object shapes into shape signatures and use shape signatures to perform similarity assessment. Several different types of shape signatures have been developed in the past. This paper provides a survey of existing algorithms for computing and comparing shape signatures. Our survey consists of a description of the desired properties of shape signatures, a scheme for classifying different types of shape signatures, and descriptions of representative algorithms for computing and comparing shape signatures. This survey concludes by identifying directions for future research.

Eumelanin-type biopolymers have attracted growing interest in the quest for soft bioinspired functional materials for application in organoelectronics. Recently, a metal-insulator-semiconductor device with a good quality interface was produced by spin coating of a com. synthetic eumelanin-like material on a dry plasma-modified silicon surface. As a proof-of-concept step toward the design and implementation of next-generation eumelanin-inspired devices, we report herein an expedient chem. strategy to bestow n-type performance to polydopamine, a highly popular eumelanin-related biopolymer with intrinsic semiconductor behavior, and to tune its elec. properties. The strategy relies on aerial co-oxidn. of dopamine with suitable arom. amines, e.g. 3-aminotyrosine or p-phenylenediamine, leading to good quality black polymeric films. Capacitance-voltage expts. on poly(dopamine/3-aminotyrosine) and poly(dopamine/p-phenylenediamine)-based metal insulator semiconductor devices on p-Si indicated a significant increase in flat band voltage with respect to polydopamine and previous synthetic eumelanin-based diodes. Variations of the flat band voltage under vacuum were obsd. for each device. These results point to polydopamine as a versatile eumelanin-type water-dependent semiconductor platform amenable to fine tuning of its electronic properties through incorporation of π-conjugating arom. amines to tailor functionality

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