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121	Characterizing optical and electrical properties of monolayer MoS2 by backside absorbing layer microscopy Ullberg, Nathan January 2020 (has links) Nanomaterials are playing an increasing role in novel technologies, and it is important to develop optical methods to characterize them in situ. To that end, backside absorbing layer microscopy (BALM) has emerged as a powerful tool, being capable to resolve sub-nanometer height profiles, with video-rate acquisition speeds and a suitable geometry to couple live experiments. In the internship, several techniques involving BALM were developed, and applied to study optical and electrical properties of the transition metal dichalcogenide (TMD) monolayer MoS2, a type of 2-dimensional (2D) crystalline semiconductor. A simulations toolkit was created in MATLAB to model BALM, a workflow to reliably extract linear intensities from the CMOS detector was realized, and 2D MoS2 was synthesized by chemical vapor deposition followed by transfer to appropriate substrates. BALM data of the 2D MoS2 was acquired and combined with simulations, giving a preliminary result for its complex refractive index at 5 optical wavelengths. In addition, the first steps towards coupling BALM with a gate biased 2D MoS2 field-effect transistor were explored. To complement BALM measurements, the grown samples were also characterized by conventional optical microscopy, scanning electron microscopy, atomic force microscopy, photoluminescence spectroscopy, and Raman spectroscopy. This work provides new additions to an existing platform of BALM techniques, enabling novel BALM experiments with nanomaterial systems. In particular, it introduces a new alternative for local extraction of optical parameters and for probing of electrical charging effects, both of which are vital in the research and development of nano-optoelectronics. backside absorbing layer microscopy BALM monolayer MoS2 TMD TMDC 2D materials nanomaterials nanotechnology refractive index extinction coefficient absorption coefficient field-effect transistor FET semiconductors optoelectronics optics raw image processing chemical vapor deposition CVD in situ characterization Nano Technology Nanoteknik Condensed Matter Physics Den kondenserade materiens fysik
122	Water Quality Device : Testing Through Electronic Measurements / Water Quality Device : Testing Through Electronic Measurements Adnan Abdu, Jihad, Lundström, Philip January 2023 (has links) Water is the source of all life, but unfortunately, the water quality is getting only worse due to many factors like overuse, contamination, indifference and even by nature itself. By identifying the problem, we are one step closer to solving the problem, and that is why an intelligent water quality device is required to examine water and detect impurities within it. In this project, we are developing a device that uses an entirely new method to measure water quality. Even though the theory behind the device is very advanced, the device is still primitive in its functions and needs development to increase the usefulness and accuracy of the measurements! / Vatten är grunden till allt liv, men tyvärr blir vattenkvaliteten bara sämre på grund av många faktorer som överanvändning, förorening, likgiltighet och till och med av naturen själv. Genom att identifiera problemet är vi ett steg närmare att lösa problemet, och detta är därför en intelligent vattenkvalitetsenhet behövs för att undersöka vattnet och hitta orenheter i det. I detta projekt utvecklar vi en apparat som använder en helt ny metod för att mäta vattenkvaliteten. Även om teorin bakom apparaten är väldigt avancerad så är apparaten fortfarande primitiv i sina funktioner och behöver utveckling för att öka användbarheten och noggrannheten i mätningarna! Water Quality Water Electronics Physics Embedded Systems Pollution Water Pollution Water Quality Device Arduino Uno Rev3 Vattenkvalitet Förorening Vatten Vattenförorening Embedded Systems Inbäddad systemteknik Annan elektroteknik och elektronik Nano Technology Nanoteknik Physical Sciences Fysik Annan geovetenskap och miljövetenskap

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Characterizing optical and electrical properties of monolayer MoS2 by backside absorbing layer microscopy

Water Quality Device : Testing Through Electronic Measurements / Water Quality Device : Testing Through Electronic Measurements