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.
Results
Showing 1 to 20 of 26 for “"Minority Carrier Lifetime"”.
-
Photoconductivity and minority carrier lifetime in tin sulfide and gallium arsenide semiconductors for photovoltaics
… simulator program (SCAPS), improvements in the minority-carrier lifetime of cell materials show not only significant improvements in cell efficiencies, but also an un-masking of improvements by other properties, which are inhibited when the lifetime is too short. This work aims to calculate the …
-
Empirical correlation of minority carrier lifetime to detect density profile in germanium on silicon heteroepitaxy
… Ge/Si interface by dopants. Using the effective minority carrier lifetime measured as a function of Ge film thickness, an empirical correlation is established between the minority carrier lifetime and the defect density in the Ge film as a function of distance from the Ge/Si interface and …
-
Purity matters : enhancing carrier transport properties in tin sulfide for photovoltaic applications by reducing impurity content
… photovoltaic applications, is hampered by poor carrier-transport properties, particularly minority-carrier lifetime. This study investigates the role of intrinsic and extrinsic crystallographic point defects on the electronic transport properties of SnS. High-purity SnS is grown via …
-
Structural defect engineering of tin (II) sulfide thin films for photovoltaics
… maximum of 32%, primarily due to a low minority-carrier lifetime. In this work, I assess the impact of structural defects and anisotropy on the minority-carrier lifetime and other key device parameters, shedding light on the path to high-efficiency SnS-based photovoltaics. SnS thin films …
-
Co-optimizing silicon solar cell processing for efficiency and throughput
… layer. Previous optimizations typically maximize minority carrier lifetime without constraining process time and device parameters. This thesis explores a novel phosphorus diffusion process in which there are no isothermal steps. The goal of this work is to demonstrate simultaneous maximization of …
-
Defect investigations in InAs/GaSb type-II strained layer superlattice
… still faces several challenges, including low minority carrier lifetime, resulting from trap levels that cause Schockley-Read-Hall recombination. These low lifetimes lead to reduced signal-to-noise ratio and higher dark current. Therefore, increasing the lifetime is important for improving this …
-
Retrograde melting in transition metal-silicon systems : thermodynamic modeling, experimental verification, and potential application
… retrograde melting to improve the electronic minority carrier lifetime of low quality silicon solar cell materials is considered.
-
Characterization and modeling of CdCl2 treated CdTe/CdS thin-film solar cells
… performance was reduced despite an increase in minority carrier lifetime values. The mechanism of reduced performance is suggested to be the formation of a low bandgap CdTe layer resulting from sulfur diffusion from the CdS layer. Sulfur diffusion primarily occurs during the CdCl2 treatment and …
-
Developing high efficiency Cu2ZnSnS4 (CZTS) thin film solar cells by sputtering
… the electrical property of CZTS film such as carrier concentration and minority carrier lifetime, thereby influencing the CZTS solar cell efficiency. Secondly, the effects of sulfurization annealing atmosphere and post-heat treatment have been studied. The “epitaxial” CdS/CZTS interface and …
-
Improving charge carrier dynamics in tin (II) sulfide through targeted defect engineering
… yet insufficient for commercial production. Low minority carrier lifetimes of <100 ps have been shown to be the root cause of this low performance, and carrier lifetimes >1 ns are predicted to enable >10%-efficient devices. In this thesis work, I employed defect modeling to identify the most …
-
Characterization of temperature profile in furnace and solubility of iron in silicon
… the in-diffused iron concentration by comparing minority carrier lifetime measurements before and after iron-boron pair (Fei-Bs) dissociation. For the thermocouple used, a furnace dwell time of 15 minutes was determined to be sufficient to reach a stable temperature. At a forming gas flow rate of …
-
Effect of Alkali on the Efficiency and Reliability of Cu(In,Ga)Se2 Solar Cells
… of E<sub>v</sub>+0.98 eV trap, higher majority carrier concentration and improved minority carrier lifetime, contributing to the experimentally observed improvement in open circuit voltage. Critical changes in alkali elemental profile occur throughout the film, while no other major …
-
Silicon cast wafer recrystallization for photovoltaic applications
… and improved dislocation density are disclosed. Minority carrier lifetime measurements are also disclosed. Although still preliminary, overall results are promising for the successful refinement of small-grained, rapid-cast wafers into large-grained, high-lifetime wafers suitable for use as …
-
Root cause defect identification in multicrystalline silicon for improved photovoltaic module reliability
… model of LeTID is proposed. Techniques including minority carrier lifetime spectroscopy, synchrotron-based X-ray fluorescence, intentional contamination, and process simulation are employed to probe the defect causing LeTID. The results indicate that LeTID is caused by at least two …
-
Defect Engineering in Cuprous Oxide (Cu₂O) Solar Cells
… processing conditions for improving mobility and minority carrier lifetime in Cu₂O. Keywords - Earth-abundant, thin-film solar cells, tandem, defect engineering, cost modeling, synchrotron.
-
STUDY AND CHARACTERIZATION OF INNOVATIVE CLEANING METHODS IN MICROELECTRONICS
… using Surface Photovoltage (SPV) minority carrier lifetime analysis and, finally, COCOS measurements have been done in order to investigate on Dit, Qtot, Qit, and Vfb after gate oxide process.
-
Electrical study of molybdenum in silicon and fluorinated SiO₂ for interlayer dielectrics
… into the forbidden gap of silicon, degrading minority carrier lifetime. In this project, DLTS was used to measure the concentration of electrically active molybdenum. Temperature dependence was investigated by varying annealing temperature and keeping annealing time constant, and time …
-
Detecting and gettering chromium impurities in photovoltaic crystalline silicon
… which has higher capture cross-sections for minority carriers and is therefore more detrimental in both p- and n-type materials. In this thesis, I employ synchrotron-based X-ray fluorescence microscopy to study chromium (Cr) distributions in multicrystalline silicon in as-grown material and …
-
Electron Injection-induced Effects In Iii-nitrides: Physics And Applications
… the impact of electron injection on the minority carrier transport and optical properties. In addition, the application of the electron injection effect in optoelectronic devices was investigated. The impact of electron injection on the minority carrier diffusion length was studied at …
-
Physical and optoelectronic properties of copper silver indium diselenide thin films
… for Ag-dominant films. An increase in the minority carrier lifetime of films with the addition of Ag also supports this conclusion. Furthermore, AgInSe2 films showed less spatial and spectral variations than Cu-containing films in cathodoluminescence measurements, indicating less …
Page 1 of 2