Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 13 of 13 for “"Hetero-junction"”.
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Optoelectronic devices based on graded bandgap structures utilising electroplated semiconductors
… in this thesis is to develop low-cost multi-junction graded bandgap solar cells using electroplated semiconductors. The semiconductor materials explored in this research are CdSe, ZnTe, CdS, CdMnTe and CdTe thin films. These layers were characterised for their structural, compositional, …
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Evaporative printing of organic materials and metals and development of organic memories
… electronic devices. Charge trapping in organic hetero-junction structures results in two distinct phenomena that both manifest as a memory behavior. Trapped charge can (1) increase the carrier mobility in organic structures, (2) generate current during the de-trapping process. Both processes are …
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Antimonide-based field-effect transistors and heterojunction bipolar transistors grown by molecular beam epitaxy
… including field effect transistors (FETs) and hetero-junction bipolar transistors (HBTs), was explored using gas-source molecular beam epitaxy (MBE). The first and second parts of the dissertation detail the growth of InAsSb and InGaSb as the channel materials for n- and p-type FETs, …
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Impact of Electrical Contacting Scheme on Performance of InGaN/GaN Schottky Solar Cells
… have recently investigated InGaN-based homo-junction and hetero-junction p-i-n solar cells. However, very few groups have worked on InGaN Schottky solar cells. Compared to p-n junctions, Schottky barrier solar cells are cheaper to grow and fabricate; they are also expected to improve the …
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Optimization and characterization of Organic Solar cells based on Regio-P3HT and C66-PCBM blends
Bulk Hetero-Junction - (BHJ) - Organic photovoltaic (OPV) cells based on the conjugated polymer poly (3-hexylthiophene-2, 5- diyl) (region-P3HT) also referred to as P3HT and a fullerene derivative [6, 6] Phenyl-C61-butyric acid methyl ester (C60-PCBM) also referred to as PCBM. The optimization, …
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Optimization and characterization of Organic Solar cells based on Regio-P3HT and C66-PCBM blends
Bulk Hetero-Junction - (BHJ) - Organic photovoltaic (OPV) cells based on the conjugated polymer poly (3-hexylthiophene-2, 5- diyl) (region-P3HT) also referred to as P3HT and a fullerene derivative [6, 6] Phenyl-C61-butyric acid methyl ester (C60-PCBM) also referred to as PCBM. The optimization, …
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Preparation Of Efficient Cuin1-xgaxse2-ysy/cds Thin-film Solar Cells By Optimizing The Molybdenum Back Contact And Using Diethylselenide as Selenium Precursor
… coated with a 50 to 60 nm thick layer of CdS as hetero-junction partner by chemical bath deposition. A window bi-layer of i:ZnO/ZnO:Al was deposited by RF magnetron sputtering. The thickness of i:ZnO was increased to reduce the shunt resistance to improve open circuit voltage. The cells were …
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Investigation of Surface States and Device Surface Charging in Nitride Materials Using Scanning Kelvin Probe Microscopy
… of a GaN Schottky diode as well as an AlGaN/GaN Hetero-junction Field Effect Transistor (HFET) show an increase of band bending near the Schottky contact edge. For an applied reverse bias of 4 V, about 0.5 eV increase of band bending was observed. This increase of band bending was caused by …
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Properties and device applications of silicon and silicon-germanium nanostructures with different dimensions
… one-dimensional (1D) Si NWs and 1D Si/Ge NW heterojunctions (HJs). Raman scattering and photoluminescence measurements show that by alternating heavily boron-doped layers with layers of undoped Si in Si/Si:B multilayers, dopant segregation and strain can be avoided. Current-voltage and …
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Thin film solar cells using all-electrodeposited ZnS, CdS and CdTe materials.
… fabricated solar cell structures of the n-n hetero-junction + large Schottky barrier type were fabricated instead of the conventional p-n junction type structure. Conventional post-deposition CdCl[2] treatment of CdTe rather carried out with a mixture of CdCl[2] and CdF[2], resulted in …
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Novel nanolasers, nano-LEDs, and modal cutoff confinement light emitters
… excellent I-V characteristics with a thin hetero-junction diode. The light output curve shows a super-linear behavior suggesting possible lasing in the cavity volume less than 3.
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Wide Bandwidth Control Electronics For Gan-Based Pebbs
… velocity, high sheet-carrier concentration at hetero-junction interfaces, high breakdown voltages, etc. These properties make the use of III-Nitride technology a promising approach for high-power, high-temperature and high-speed applications in power electronics, and make GaN power devices a …
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Enhancing light-matter interactions in oxide semiconductors
… give rise to an application of surface homojunction for the materials that have limited tunability in their properties. Second, I demonstrate an approach to utilize a significant portion of visible light spectrum by combining anatase TiO2 with anomalously high light-absorbing metallic …