Copper films with a thickness in the nanometer range are required as seed layers for the electrochemical Cu deposition to form multilevel interconnects in ultralarge-scale integrated (ULSI) electronic devices. Continuously shrinking device dimensions and increasing aspect ratios of the dual-damascene structures in the copper-based metallization schemes put ever more stringent requirements on the films with respect to their conformality in nanostructures and thickness homogeneity across large wafers. Due to its intrinsic self-limiting film growth characteristic, atomic layer deposition (ALD) appears appropriate for homogeneously coating complex substrates and to replace conventional physical vapor deposition (PVD) methods beyond the 32 nm technology node. To overcome issues of direct Cu ALD, such as film agglomeration at higher temperatures or reduced step coverage in plasma-based processes, an ALD copper oxide film may be grown under mild processing conditions, while a subsequent reduction step converts it to metallic copper. In this poster, which was presented at the AVS 9th International Conference on Atomic Layer Deposition (ALD 2009), held in Monterey, California from 19 to 22 July 2009, we report detailed film growth studies of ALD copper oxide in the self-limiting regime on SiO2, TaN and Ru. Applications in subsequent electrochemical deposition processes are discussed, comparing Cu plating results on as-deposited PVD Ru as well as with PVD and reduced ALD Cu seed layer.

Copper-based multi-level metallization systems in today’s ultralarge-scale integrated electronic circuits require the fabrication of diffusion barriers and conductive seed layers for the electrochemical metal deposition. Such films of only several nanometers in thickness have to be deposited void-free and conformal in patterned dielectrics. The envisaged further reduction of the geometric dimensions of the interconnect system calls for coating techniques that circumvent the drawbacks of the well-established physical vapor deposition. The atomic layer deposition method (ALD) allows depositing films on the nanometer scale conformally both on three-dimensional objects as well as on large-area substrates. The present work therefore is concerned with the development of an ALD process to grow copper oxide films based on the metal-organic precursor bis(tri-n-butylphosphane)copper(I)acetylacetonate [(nBu3P)2Cu(acac)]. This liquid, non-fluorinated β-diketonate is brought to react with a mixture of water vapor and oxygen at temperatures from 100 to 160°C. Typical ALD-like growth behavior arises between 100 and 130°C, depending on the respective substrate used. On tantalum nitride and silicon dioxide substrates, smooth films and self-saturating film growth, typical for ALD, are obtained. On ruthenium substrates, positive deposition results are obtained as well. However, a considerable intermixing of the ALD copper oxide with the underlying films takes place. Tantalum substrates lead to a fast self-decomposition of the copper precursor. As a consequence, isolated nuclei or larger particles are always obtained together with continuous films. The copper oxide films grown by ALD can be reduced to copper by vapor-phase processes. If formic acid is used as the reducing agent, these processes can already be carried out at similar temperatures as the ALD, so that agglomeration of the films is largely avoided. Also for an integration with subsequent electrochemical copper deposition, the combination of ALD copper and ruthenium proves advantageous, especially with respect to the quality of the electroplated films and their filling behavior in interconnect structures. Furthermore, the ALD process developed also bears potential for an integration with carbon nanotubes. / Kupferbasierte Mehrlagenmetallisierungssysteme in heutigen hochintegrierten elektronischen Schaltkreisen erfordern die Herstellung von Diffusionsbarrieren und leitfähigen Keimschichten für die galvanische Metallabscheidung. Diese Schichten von nur wenigen Nanometern Dicke müssen konform und fehlerfrei in strukturierten Dielektrika abgeschieden werden. Die sich abzeichnende weitere Verkleinerung der geometrischen Dimensionen des Leitbahnsystems erfordert Beschichtungstechnologien, die vorhandene Nachteile der bisher etablierten Physikalischen Dampfphasenabscheidung beheben. Die Methode der Atomlagenabscheidung (ALD) ermöglicht es, Schichten im Nanometerbereich sowohl auf dreidimensional strukturierten Objekten als auch auf großflächigen Substraten gleichmäßig herzustellen. Die vorliegende Arbeit befasst sich daher mit der Entwicklung eines ALD-Prozesses zur Abscheidung von Kupferoxidschichten, ausgehend von der metallorganischen Vorstufe Bis(tri-n-butylphosphan)kupfer(I)acetylacetonat [(nBu3P)2Cu(acac)]. Dieses flüssige, nichtfluorierte β-Diketonat wird bei Temperaturen zwischen 100 und 160°C mit einer Mischung aus Wasserdampf und Sauerstoff zur Reaktion gebracht. ALD-typisches Schichtwachstum stellt sich in Abhängigkeit des gewählten Substrats zwischen 100 und 130°C ein. Auf Tantalnitrid- und Siliziumdioxidsubstraten werden dabei sehr glatte Schichten bei gesättigtem Wachstumsverhalten erhalten. Auch auf Rutheniumsubstraten werden gute Abscheideergebnisse erzielt, jedoch kommt es hier zu einer merklichen Durchmischung des ALD-Kupferoxids mit dem Untergrund. Tantalsubstrate führen zu einer schnellen Selbstzersetzung des Kupferprecursors, in dessen Folge neben geschlossenen Schichten während der ALD auch immer isolierte Keime oder größere Partikel erhalten werden. Die mittels ALD gewachsenen Kupferoxidschichten können in Gasphasenprozessen zu Kupfer reduziert werden. Wird Ameisensäure als Reduktionsmittel genutzt, können diese Prozesse bereits bei ähnlichen Temperaturen wie die ALD durchgeführt werden, so dass Agglomeration der Schichten weitgehend verhindert wird. Als besonders vorteilhaft für die Ameisensäure-Reduktion erweisen sich Rutheniumsubstrate. Auch für eine Integration mit nachfolgenden Galvanikprozessen zur Abscheidung von Kupfer zeigen sich Vorteile der Kombination ALD-Kupfer/Ruthenium, insbesondere hinsichtlich der Qualität der erhaltenen galvanischen Schichten und deren Füllverhalten in Leitbahnstrukturen. Der entwickelte ALD-Prozess besitzt darüber hinaus Potential zur Integration mit Kohlenstoffnanoröhren.

The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.

In this work, an approach for copper atomic layer deposition (ALD) via reduction of CuxO films was investigated regarding applications in ULSI interconnects, like Cu seed layers directly grown on diffusion barriers (e. g. TaN) or possible liner materials (e. g. Ru or Ni) as well as non-ferromagnetic spacer layers between ferromagnetic films in GMR sensor elements, like Ni or Co. The thermal CuxO ALD process is based on the Cu (I) β-diketonate precursor [(nBu3P)2Cu(acac)] and a mixture of water vapor and oxygen ("wet O2") as co-reactant at temperatures between 100 and 130 °C. Highly efficient conversions of the CuxO to metallic Cu films are realized by a vapor phase treatment with formic acid (HCOOH), especially on Ru substrates. Electrochemical deposition (ECD) experiments on Cu ALD seed / Ru liner stacks in typical interconnect patterns are showing nearly perfectly filling behavior. For improving the HCOOH reduction on arbitrary substrates, a catalytic amount of Ru was successful introduced into the CuxO films during the ALD with a precursor mixture of the Cu (I) β-diketonate and an organometallic Ru precursor. Furthermore, molecular and atomic hydrogen were studied as promising alternative reducing agents.

Atomic layer deposition (ALD) of copper films is getting enormous interest. Ultrathin Cu films are applied as the seed layer for electrochemical deposition (ECD) of copper in interconnect circuits and as the non-magnetic material for the realization of giant magnetoresistance (GMR) sensors. Particularly, Co/Cu multi-layered structures require sub 4.0 nm copper film thickness for obtaining strong GMR effects. The physical vapor deposition process for the deposition of the copper seed layers are prone to non-conformal coating and poor step coverage on side-walls and bottoms of trenches and vias, and presence of overhanging structures. This may cause failure of interconnections due to formation of voids after copper ECD. ALD is the most suitable technology for the deposition of conformal seed layers for the subsequent ECD in very high aspect ratio structures, also for the technology nodes below 20 nm. Surface chemistry during the ALD of oxides is quite well studied. However, surface chemistry during the ALD of pure metal is rather immature. This knowledge is necessary to optimize the process parameters, synthesize better precursors systems, and enhance the knowledge of existing metal ALD processes. The major goal of this work is to understand the surface chemistry of the used precursor and study the growth of ultrathin copper films using in-situ X-ray photoelectron spectroscopy (XPS). Copper films are deposited by ALD using the precursor mixture consisting of 99 mol% [(nBu3P)2Cu(acac)], as copper precursor and 1 mol% of Ru(η5 C7H11)(η5 C5H4SiMe3), as ruthenium precursor. The purpose in having catalytic amount of ruthenium precursor is to obtain the Ru doped Cu2O layers for subsequent reduction with formic acid at temperatures below 150 °C on arbitrary substrates. Two different approaches for the growth of ultrathin copper films have been studied in this dissertation. In the first approach, direct thermal ALD of copper has been studied by using H2 as co-reactant on Co as catalytic substrate. In the second approach, Ru-doped Cu2O is deposited by ALD using wet-O2 as co-reactant on SiO2 as non-catalytic substrate. The Ru-doped Cu2O is successfully reduced by using either formic acid or carbon-monoxide on SiO2. / Atomlagenabscheidung (ALD) von Kupfer steht im Fokus der ALD Gemeinschaft. Ultradünne Kupferschichten können als Keimschicht für die elektrochemische Abscheidung (ECD) von Kupfer in der Verbindungstechnologie eingesetzt werden. Sie können ebenfalls für Sensoren, welche auf den Effekt des Riesenmagnetowiderstandes (GMR) basieren, als nicht-ferromagnetische Zwischenschicht verwendet werden. Insbesondere Multischichtstrukturen aus ferromagnetische Kobalt und Kupfer erfordern Schichtdicken von weniger als 4,0 nm, um einen starken GMR-Effekt zu gewährleisten. Das derzeit verwendete physikalische Dampfabscheidungsverfahren für ultradünne Kupferschichten, ist besonders anfällig für eine nicht-konforme Abscheidung an den Seitenwänden und Böden von Strukturen mit hohem Aspektverhältnis. Des Weiteren kann es zur Bildung von Löchern und überhängenden Strukturen kommen, welche bei der anschließenden Kupfer ECD zu Kontaktlücken (Voids) führen können. Für die Abscheidung einer Kupfer-Keimschicht ist die ALD besonders gut geeignet, da sie es ermöglicht, ultradünne konforme Schichten auf strukturierten Oberflächen mit hohem Aspektverhältnis abzuscheiden. Dies macht sie zu einer der Schlüsseltechnologien für Struckturgrößen unter 20 nm. Im Gegensatz zur Oberflächenchemie rein metallischer ALD sind die Oberflächenreaktionen für oxidische ALD Schichten sehr gut untersucht. Die Kenntnis der Oberflächenchemie während eines ALD Prozesses ist essenziel für die Bestimmung von wichtigen Prozessparametern als auch für die Verbesserung der Präkursorsynthese ansich. Diese Arbeit beschäftigt sich mit der Untersuchung der Oberflächenchemie und Charakterisierung des Wachstums von ultradünnen Metall-Cu-Schichten mittels In-situ XPS, welche eines indirekten (Oxid) bzw. direkten Metall-ALD Prozesses abgeschieden werden, wobei die Kupfer-Oxidschichten im Anschluss einem Reduktionsprozess unterworfen werden. Hierfür wird eine Präkursormischung bestehend aus 99 mol% [(nBu3P)2Cu(acac)] und 1 mol% [Ru(η5 C7H11)(η5-C5H4SiMe3)] verwendet. Die katalytische Menge an Ru, welche in der entstehenden Cu2O Schicht verbleibt, erhöht den Effekt der Reduktion der Cu2O Schicht auf beliebigen Substraten mit Ameinsäure bei Wafertemperaturen unter 150 °C. In einem ersten Schritt wird ein direkter thermisches Kupfer ALD-Prozess, unter Verwendung von molekularem Wasserstoff als Coreaktant, auf einem Kobalt-Substrat untersucht. In einem zweiten Schritt wird ein indirekter thermischer Cu2O-ALD-Prozess, unter gleichzeitiger Verwendung von Sauerstoff und Wasserdampf als Coreaktant, mit anschließender Reduktion durch Ameinsäure oder Kohlenstoffmonoxid zu Kupfer auf den gleichen Substraten betrachtet. Die vorliegende Arbeit beschreibt das Wachstum von ultradünnen und kontinuierlichen Kupfer-Schichten mittels thermischer ALD auf inerten- SiO2 und reaktiven Kobalt-Substraten.

The objective of this project was to study the influence of increased salinities on interaction processes in the system radionuclide – organics – clay – aquifer. For this purpose, complexation, redox, sorption, and diffusion studies were performed under variation of the ionic strength (up to 4 mol/kg) and the background electrolyte. The U(VI) complexation by propionate was studied in dependence on ionic strength (up to 4 mol/kg NaClO4) by TRLFS, ATR FT-IR spectroscopy, and DFT calculations. An influence of ionic strength on stability constants was detected, depending on the charge of the respective complexes. The conditional stability constants, determined for 1:1, 1:2, and 1:3 complexes at specific ionic strengths, were extrapolated to zero ionic strength. The interaction of the bacteria Sporomusa sp. MT-2.99 and Paenibacillus sp. MT-2.2 cells, isolated from Opalinus Clay, with Pu was studied. The experiments can be divided into such without an electron donor where biosorption is favored and such with addition of Na-pyruvate as an electron donor stimulating also bioreduction processes. Moreover, experiments were performed to study the interactions of the halophilic archaeon Halobacterium noricense DSM-15987 with U(VI), Eu(III), and Cm(III) in 3 M NaCl solutions. Research for improving process understanding with respect to the mobility of multivalent metals in systems containing humic matter was focused on the reversibility of elementary processes and on their interaction. Kinetic stabilization processes in the dynamics of humate complexation equilibria were quantified in isotope exchange studies. The influence of high salinity on the mobilizing potential of humic-like clay organics was systematically investigated and was described by modeling. The sorption of Tc(VII)/Tc(IV) onto the iron(II)-containing minerals magnetite and siderite was studied by means of batch sorption experiments, ATR FT-IR and X-ray absorption spectroscopy. The strong Tc retention at these minerals could be attributed to surface-mediated reduction of Tc(VII) to Tc(IV). An influence of ionic strength was not observed. The influence of ionic strength (up to 3 mol/kg) and background electrolyte (NaCl, CaCl2, MgCl2) on U(VI) sorption onto montmorillonite was studied. The U(VI) sorption is influenced by the background electrolyte, the influence of ionic strength is small. Surface complexation modeling was performed applying the 2SPNE SC/CE model. Surface complexation constants were determined for the NaCl and CaCl2 system and were extrapolated to zero ionic strength. Surface complexation in mixed electrolytes can be modeled applying surface complexation constants derived for pure electrolytes. The influence of citrate on U(VI) diffusion in Opalinus Clay was studied using Opalinus Clay pore water as background electrolyte. The diffusion parameter values obtained for the HTO through-diffusion and the U(VI) in-diffusion in the absence of citric acid were in agreement with literature data. In the presence of citric acid, U(VI) diffusion was significantly retarded, which was attributed to a change in speciation, probably U(VI) was reduced to U(IV). Larger-scale heterogeneous material effects on diffusive transport were investigated with PET. Diffusion parameters were derived by optimum fit of a FEM-model to the measurement. These parameters are in accordance with the results from 1D-through-diffusion experiments. Deviations from the simple transversal-isotropic behavior, which are identified as residuals from the model, are indications for heterogeneous transport on the mm-scale. PET measurements were also conducted in order to display the improvement of the EDZ with waterglass injections. These experiments enable to draw conclusions on the complex reactive transport process and thus an estimation of the achieved improvement of the barrier function. The image reconstruction procedure was largely improved, mainly with the aid of Monte-Carlo simulations, and now allows quantitative analysis and error estimation.

Slags plays a significant role at high temperature processes. The estimation of the slag viscosity is vital for the safe run of e.g. entrained flow gasifiers. One opportunity of determination is rotational viscometry. This technique is disadvantageous in view of elevated temperatures, applied materials and the necessary time. Additionally, the viscosity can be predicted by the help of viscosity models, where viscosity is a function of slag composition and temperature. Due to changing slag properties within the technical processes, the calculated viscosities can hugely differ from measured ones. In this work, the viscosities of 42 slags where measured up to 100 Pa s and temperatures up to 1700 °C. Oxidizing and reducing conditions were applied. Additionally, selected slag samples were quenched at defined temperatures to qualitatively and quantitatively determine the formed minerals by X-ray diffraction (XRD). Differential temperature analysis (DTA) was applied to find the onset of crystallization for the complementation of investigations. The Einstein-Roscoe equation was chosen to improve the classic viscosity models. Reducing atmosphere decreased viscosity and the number of formed minerals was increased. Slags show a shear-thinning behavior above ca. 10 vol.-% of solid mineral matter. Also, Newtonian behavior was observed up to 60 vol.-%. To overcome problems with the kinetic cooling behavior of the slags, a viscosity approximation method was applied afterwards. This can result in optimized viscosity predictions when several preconditions are fulfilled.:List of Tables ............................................................................................................ vi List of Figures ........................................................................................................ viii Symbols and Abbreviations .................................................................................. xviii 1. Introduction and Aim ....................................................................................... 1 2. General Overview of Slag ............................................................................... 2 2.1 Viscosity ...................................................................................................... 2 2.1.1 Viscosity Introduction ........................................................................... 2 2.1.2 Flow behavior of fluids ......................................................................... 3 2.2 Slag Definition and Phase Diagrams ........................................................... 4 2.3 Solid Slag Structure .................................................................................... 5 2.4 Liquid Slag Structure ................................................................................. 10 2.5 Basicity and B/A-ratio ................................................................................ 11 2.6 Slag Components...................................................................................... 13 2.6.1 Silicon dioxide .................................................................................... 13 2.6.2 Aluminum oxide ................................................................................. 13 2.6.3 Calcium oxide .................................................................................... 15 2.6.4 Iron oxide ........................................................................................... 16 2.6.5 Magnesium Oxide .............................................................................. 18 2.6.6 Potassium Oxide ................................................................................ 19 2.6.7 Sodium Oxide .................................................................................... 20 2.6.8 Titanium Oxide ................................................................................... 21 2.6.9 Phosphorous ...................................................................................... 22 2.6.10 Sulfur .............................................................................................. 22 2.7 Summary of Last Chapters ........................................................................ 23 3. Slag Viscosity Toolbox .................................................................................. 25 3.1 Slag Viscosity Predictor............................................................................. 25 3.2 Slag Viscosity Database............................................................................ 26 3.3 Prediction Quality of Viscosity Models ....................................................... 27 4. Classic Slag Viscosity Modelling ................................................................... 30 4.1 Selected Classic Viscosity Models ............................................................ 31 4.1.1 S2 ....................................................................................................... 32 4.1.2 Watt-Fereday ..................................................................................... 32 4.1.3 Bomkamp ........................................................................................... 32 4.1.4 Shaw .................................................................................................. 32 4.1.5 Lakatos .............................................................................................. 33 4.1.6 Urbain ................................................................................................ 33 4.1.7 Riboud ............................................................................................... 33 4.1.8 Streeter .............................................................................................. 34 4.1.9 Kalmanovitch-Frank ........................................................................... 34 4.1.10 BBHLW .......................................................................................... 34 4.1.11 Duchesne ....................................................................................... 34 4.1.12 ANNliq ............................................................................................ 35 4.2 Need of Improvement in Viscosity Literature ............................................. 35 4.3 Summary of Last Chapters ........................................................................ 36 5. Advanced Slag Viscosity Modelling .............................................................. 37 5.1 Crystallization ............................................................................................ 37 5.1.1 Nucleation .......................................................................................... 38 5.1.2 Crystallization Rate ............................................................................ 39 5.1.3 Crystallization Measurement Methods ............................................... 39 5.2 Slag Properties Changes During Crystallization ........................................ 40 5.2.1 Slag Density ....................................................................................... 40 5.2.2 Solid Volume Fraction ........................................................................ 46 5.2.3 Estimation of Slag Composition During Cooling ................................. 46 5.3 Viscosity Depending on Particles and Shear Rate..................................... 47 5.3.1 Einstein-Roscoe Equation .................................................................. 48 5.3.2 Improved Modelling Approach by Modified Einstein-Roscoe .............. 49 5.4 Summary of Last Chapters ........................................................................ 50 6. Experimental Procedures ............................................................................. 52 6.1 Viscosity Measurements ........................................................................... 52 6.1.1 Estimating Parameter Ranges of Viscosity Measurements ................ 53 6.1.2 Viscosity Measurement Procedure ..................................................... 54 6.2 Thermal Analysis of Slags ......................................................................... 55 6.2.1 Experimental Conditions of DTA ........................................................ 55 6.3 Phase Determination ................................................................................. 55 6.3.1 Quench Experiment Processing ......................................................... 56 6.3.2 Phase Determination on XRD Results ............................................... 56 6.4 Summary of Last Chapters ........................................................................ 57 7. Results and Discussion ................................................................................ 58 7.1 Selected Slag Samples ............................................................................. 58 7.1.1 Slag Sample Composition Before Viscosity Measurements ............... 58 7.1.2 Slag Sample Composition After Viscosity Measurements .................. 59 7.2 General Results of Viscosity Measurements ............................................. 60 7.2.1 Viscosity under Air Atmosphere ......................................................... 63 7.2.2 Viscosity under Reducing Atmospheres ............................................. 65 7.2.3 Viscosity under Constant Partial Oxygen Pressure ............................ 66 7.2.4 Summary of Last Chapter .................................................................. 68 7.3 Mineral Formation ..................................................................................... 69 7.3.1 General Results on Primarily Mineral Formation ................................ 69 7.3.2 Influences on Primarily Mineral Formation ......................................... 70 7.3.3 Mineral Formation over Wide Temperature Ranges ........................... 71 7.3.4 Summary of Last Chapter .................................................................. 77 7.4 Results Obtained by DTA .......................................................................... 78 7.4.1 Comparing Results obtained by DTA and Quenching ........................ 80 7.4.2 Summary of Last Chapter .................................................................. 82 7.5 Shear Rate Influence on Slag Viscosity ..................................................... 82 7.5.1 Shear Rate Influence under Oxidizing Atmospheres .......................... 83 7.5.2 Shear Rate Influence under Reducing Atmospheres .......................... 87 7.5.3 Shear Rate Influence under Constant Atmospheres .......................... 91 7.5.4 Summary of chapter ........................................................................... 92 7.6 Atmospheric Influence on Viscosity ........................................................... 93 7.6.1 Summary of Last Chapter .................................................................. 95 7.7 Cooling Rate Influence on Slag Viscosity .................................................. 95 7.7.1 Summary of Last Chapter .................................................................. 97 8. Advanced Viscosity Modelling Approach ...................................................... 99 8.1 Prediction Quality of Classical Viscosity Models ........................................ 99 8.1.1 Selecting the Best Viscosity Model for Newtonian Flow ..................... 99 8.1.2 Summary of Last Chapter ................................................................ 103 8.2 Predicting Liquidus Temperature ............................................................. 103 8.2.1 Comparing Liquidus Calculations and Quenching Experiments ....... 103 8.2.2 Comparing DTA Results and Liquidus Calculations ......................... 105 8.2.3 Summary of Last Chapter ................................................................ 107 8.3 Predicting Liquid Slag Composition ......................................................... 108 8.3.1 Results of Slag Composition Calculations at Oxidizing Conditions ... 108 8.3.2 Results of Slag Composition Calculations at Reducing Conditions ... 110 8.3.3 Summary of Last Chapter ................................................................ 111 8.4 Modelling Approach ................................................................................ 112 8.4.1 Development of Datasets for Advanced Viscosity Modeling ............. 113 8.4.2 Summary of Last Chapter ................................................................ 116 8.5 Results of Advanced Slag Viscosity Modelling Approach ........................ 116 8.5.1 Summary of Last Chapter ................................................................ 121 9. Summary .................................................................................................... 123 10. Appendix: Information on Classic Viscosity Modelling ................................. 126 10.1 Backgrounds of Applied Viscosity Models............................................ 126 10.2 Viscosity Model of the BCURA (S2) ..................................................... 129 10.3 Watt-Fereday ....................................................................................... 130 10.4 Bomkamp ............................................................................................ 130 10.5 Shaw ................................................................................................... 131 10.6 Lakatos Model ..................................................................................... 132 10.7 Urbain Model ....................................................................................... 133 10.8 Riboud Model ...................................................................................... 134 10.9 Streeter Model ..................................................................................... 136 10.10 Kalmanovitch-Frank Model .................................................................. 137 10.11 BBHLW Model ..................................................................................... 137 10.12 Duchesne Model .................................................................................. 139 10.13 ANNliq Model ...................................................................................... 141 11. Appendix: Settings of Equilibrium Calculations ........................................... 143 12. Appendix: Parameters of Einstein-Roscoe Equation ................................... 153 13. Appendix: Ash and Slag Sample Preparation ............................................. 155 14. Appendix: Experimental Procedures: Viscometer ....................................... 159 14.1 General Viscometer Description .......................................................... 159 14.2 Temperature Calibration ...................................................................... 160 14.3 Viscometer Calibration ......................................................................... 160 14.4 Accuracy and Reproducibility of HT-Viscosity Measurements .............. 161 14.5 Influence of Inductive Heating .............................................................. 163 14.6 Influence of Measurement System Materials ....................................... 164 15. Appendix: Experimental Procedures: Quenching Furnace .......................... 167 16. Appendix: Slag Sample Parameters and Composition ................................ 168 17. Appendix: Slag Viscosity Measurements Results ....................................... 175 18. Appendix: Viscosities at Different Cooling Rates ........................................ 182 19. Appendix: Slag Viscosity Modelling: AALE Calculations ............................. 187 20. Appendix: Advanced Viscosity Modelling: a-factors .................................... 193 21. Appendix: Slag Mineral Phase Investigations and Modelling ...................... 197 22. Appendix: Results of DTA Measurements on Slags .................................... 207 23. Appendix: Advanced Slag Viscosity Modelling Approach ............................ 211 References ........................................................................................................... 228

A method of producing steel that is not used in Sweden today is direct reduction using natural gas, a method which could has enormous potential in the future of steelmaking. Historically, steelmaking prioritized productivity and profitability. However, other aspects such as safety, sustainability, and environmentally friendliness have become increasingly important to Swedish steelmakers. This study evaluates the usage of natural gas to  directly reduce iron ore into the porous form known as iron sponge, then finally processing that sponge into crude steel. The technology available today is assessed through a literature review, then two calculative data-based model: using DRI sponge in a traditional integrated steelmaking line or replacing steel scrap with it in an electric arc furnace. While this technology is used in many regions where natural gas is plentiful, it has not yet been used in Sweden. Now, when the Swedish natural gas network is expanding and the vehicular transportation of liquid natural gas is becoming more and more viable, it is a prime situation to evaluate direct reduction in Sweden. While models require assumptions and estimations, they suggest that DRI will absolutely be a viable option in the years to come. Integrated plant operators can reduce their immense carbon emissions for a reasonable price, while DRI sponge melting in an electrical arc furnace can either help steelmakers escape the volatile scrap market or be used to replace the blast furnace as a whole in the future. / En metod för att producera stål som inte används i Sverige idag är direkt reduktion med hjälp av naturgas, en metod som har en enorm potential i framtida ståltillverkning. Historiskt har ståltillverkningen prioriterat produktivitet och vinst, men säkerhet, hållbarhet, och miljövänlighet har blivit områden mer och mer viktiga för svenska ståltillverkare. Den här studien utvärderar användningen av naturgas för att direkt reducera järnmalm till den porösa formen känd som järnsvamp, och sen bearbeta den till primärt stål. Teknologin som flnns idag utvärderas genom en litteraturstudie, vars data beräknas till två scenariomodeller: användningen av järnsvamp i ett traditionellt integrerat stålverk eller genom att ersätta stålskrot med järnsvamp i ljusbågsungen. Den här teknologin används redan idag i regioner där naturgas är lättillgängligt, men har hittills inte använts i Sverige. Men nu när Sveriges naturgasnät byggs ut och fordonstransporterad flytande naturgas blir mer och mer kostnadseffektiv så är det lämpligt att utvärdera direkt reduktion i Sverige. Modellerna kräver antaganden och uppskattningar, men de pekar på att direkt reducering av järnmalm kommer att vara en genomförbar metod för ståltillverkning i en nära framtid. Integrerade masugnslinjer kan minska sina enorma koldioxidutsläpp till ett rimligt pris, och järnsvampssmältning i ljusbågsugn kan hjälpa ståltillverkare att undanfly den instabila stålskrotsmarknaden eller användas för att helt ersätta masugnsproduktion i framtiden.

Pluvial floods are the most difficult and to date least investigated phenomena in urban hydrology. While efforts are being made to increase the knowledge base concerning this type of flooding, a large part of the difficulty lies in the nature of the precipitation. Convective storms represent most of the larger intensity short term rainfall in urban areas and is also the raintype, that is expected to increase the most in the future. The rain cells of this type have a more distinct boundary, larger intensity, a smaller extent and a shorter life span, than frontal rains. Combined with the low availability of densely spaced rain gauge networks and also low temporal resolution of measurements in 15 minutes intervals at best, makes this rain type still very difficult to analyze and even harder to predict. The resolution of cloud radar images at 2x2km and taken every 15 minutes is too coarse and the error reduction algorithms for radar based precipitation (HIPRAD) images to analysera in patterns are not sufficient by them selves to analyze the characteristics of such rainfields and the processes occurring within these fields. The spatial variation of raincells, their development and decay, the distance between them, and the velocity and direction of their movement can however be investigated employing a combination of densely spaced rain gauges and radar images to reach a more realistic representation of short-term precipitation for the use of in hydraulic models. The movement of rain fields has been investigated with two main areas of focus: The influence of direction or directional bias, often with an interest in the most crucial case referred to as the resonance effect, and in context of areal reduction of point rainfall. Most of these studies have been carried out with statistical methods and in laboratory experiments. In this study a hydraulic model was built on the terrain model of a realcity, a 28 km area in the city of Falun, to test the recently gathered information about the temporal variation of five empirical hyetographs with different peak arrival times and peak intensities, which are representative of Swedish climate. The hyetographs were produced and provided by SMHI. The empirical rain types were derived from 20 years of rain gauge observations and confirmed by radar images. For reference purposes, a standard Chicago design storm (CDS) rain was modeled as well. The simulated scenarios were modeled as a MIKE 21 hydraulic model, as a stationary scenario and in four movement directions. It was foundthat the empirical rain types produced lower inundation depth than the CDS, in a range of 20 to 50 % lower. The effect of modeling rainfall in motion produced on average only about 4-20 % lower water depths than the corresponding non-moving scenario. In a few instances, in a single evaluation point, the moving scenarios resulted in a relative water depth of a maximum of just above 1%. It was concluded that the conceptual approach of areal reduction from movement seems to be accurate and could help improve modeling rainfall in general, and specifically for cloud burst scenarios of shorter durations in urban catchments. It was also found that further investigation of the physical processes in rainfields could serve to increase the accuracy in areal reduction of precipitation for more realistic hydraulic models and in turn reduce over design. / Pluviala översvämningar är den typen, som är både svårast att reda ut och samtidigt den minst utforskade fenomenen inom urban hydrologi. Medan ansträngningar görs för att förbättra kunskapsläget, ligger den största svårigheten i nederbördens skepnad. Det är konvektiva regn som utgör de flesta av de starkare korttids regntillfällen i urbana områden och är också regntypen som förväntas att öka mest i framtiden. Regncellerna har en tydligare avgränsning, en större intensitet, mindre utsträckning, och en kortare livscykel än frontala regn. I kombination med den låga tillgängligheten av regnmätarnätverk med hög täthet i positioneringen av mätare, samt den låga tidsupplösningen av mätningar i intervaller av 15 minuter gör att konvektiva regn fortfarande är svåra att analysera och ännu svårare att förutse. Upplösningen av molnradar bilder av 2x2 km som tas varje 15:de minut är för grova och algoritmer för felreducering av bilder från radarbaserad nederbördsdata (HIPRAD) för analys av regn mönster är inte tillräckligt noggranna, för sig, för att kunna analysera egenskaperna av sådana regnfält och de processerna som karakteriserar dessa. Den spatiala variationen inom regnceller, deras utveckling och förfall, avståndet mellan dem samt riktningen och hastigheten kan ändå undersökas med hjälp av kombinationen av regnmätarnätverk och radar bilder för att uppnå mer realistiska korttids nederbördsscenarier för användning i hydrauliska model. Studier, som har undersökt regn i rörelse har varit fokuserade på två huvudområden: Betydelsen av riktningen, i vilken regnet rör sig, där den största effekten som denna riktningsbias kan uppnå, har döpts resonans effekt och i samband med ytreducering (areal reduction) av punkt nederbörd. De flesta av dessa studier har genomförts med hjälp av statistiska metoder och laboratorieexperiment. I denna studie skapades en hydraulisk modell baserad på en realistisk terräng av ett existerade urbant område, en yta på 28 km i Falun, för att testa den nyligen utvärderade informationen om temporala intensitets fördelningen som representerar det svenska klimatet. Regndatat producerades och tillhandahölls av SMHI och representerar en mätserie från regnmätare över en period av 20 år. Som referens modellerades även ett Chicago regn (CDS). Med hjälp av en MIKE21 hydraulisk modell, simulerades ett stationärt scenario och fyra rörelseriktningar för varje empirisk hyetograf. Resultaten visade att de empiriska regntyperna skapade översvämningar med 20-50% lägre vattendjup än CDS regnet. Att modellera rörelsen resulterade i 4-20% lägre vattennivåer jämfört med respektive stationär scenario. I några enstaka tillfällen, i en av evalueringspunkterna, skapade de rörliga scenarierna större resultat, med lite över 1% i det största fallet. Det drogs slutsatsen att konceptet av areal reduction genom molnrörelse verkar vara korrekt och skulle kunna hjälpa att förbättra sättet att modellera regn generellt, men också specifikt för skyfalls scenarier med korta varaktigheter över urbana avrinningsområden. Man kom ytterligare till slutsatsen att framtida studier i samband med de fysiska processerna i regnceller skulle kunna användas för att höja noggrannheten av ytreducering av nederbörd för mer realistiska hydrauliska modeller, som i sin tur kunde minska överdesign.

This thesis is a collaboration with Stockholm Globe Arena Fastigher AB (SGAF) and focuses on a case study involving the multi-functional arenas Avicii Arena and Annexet in Stockholm, Sweden. The objective of this study is to investigate Key Performance Indicators (KPI) that can sufficiently measure and evaluate monthly and yearly electricity, heating and cooling consumption while considering events and visitors. Data regarding visitor and event, electricity, heating and cooling were provided by companies in agreement with SGAF, which is handled in a Data Reduction. This study identified four different KPIs to evaluate energy consumption dynamics; KPI 1: Energy consumption per event day, KPI 2: Energy consumption per visitor, KPI 3: Load Factor and KPI 4: Occupancy rate. The results showed that the monthly KPI 1 and 2 values exhibited unpredictable fluctuations hindering its ability to assess energy consumption patterns. In contrast, the annual KPI 1 and 2 were able to effectively evaluate the energy consumption which uncovered that the electricity consumption in the venues is on a downward trend. However, the heating and cooling consumption remained stagnant during the same timeframe. KPI 3 and 4 displayed efficient operation of the energy systems. Moreover, all four KPIs revealed that the energy consumption is influenced by other factor beyond visitors and events. A subsequent Correlation Analysis unveiled two additional factors, outdoor temperature and event types, affects the energy consumption which suggests potential areas for future research. / Detta examensarbete ar ett samarbete med Stockholm Globe Arena Fastigheter AB (SGAF) och fokuserar på en fallstudie som involverar de multi-funktionella arenorna Avicii Arena och Annexet i Stockholm, Sverige. Målet med denna studie är att undersöka Nyckeltal som kan mäta och utvärdera månatlig och årlig elektricitetsförbrukning, värmeförbrukning och kylförbrukning med hänsyn till evenemang och besökare. Data avseende besökare och evenemang, elförbrukning, värmeförbrukning och kylförbrukning tillhandahölls av företag i samförstånd med SGAF som hanterades i en Data Reduktion. Denna studie identifierade fyra olika nyckeltal för utvärdering av energiförbrukningen; Nyckeltal 1: Energiförbrukning per evenemangsdag, Nyckeltal 2: Energiförbrukning per besökare, Nyckeltal 3: Belastningsfaktor och Nyckeltal 4: Beläggningsgrad. Resultaten visar att de månatliga nyckeltalen 1 och 2 uppvisade förutsägbara fluktuationer som hindrade dess förmåga att bedöma energiförbrukningsmönster. Den årliga nyckeltalen 1 och 2 kunde effektivt utvärdera energiförbrukningen vilket avslöjade att elförbrukningen i anläggningarna minskar. Dock, påvisade värmeförbrukningen och kylförbrukningen oförändrade under samma tidsperiod. Nyckeltal 3 och 4 uppvisade att energisystemen i anläggningarna körs på ett effektivt sätt. Vidare, visade samtliga fyra nyckeltal att energiförbrukningen påverkas av andra faktorer utöver besökare och evenemang. En efterföljande korrelationsanalys påvisar att två ytterligare faktorer, utomhus temperatur och evenemangstyper, påverkar energiförbrukningen vilket antyder nya potentiella forskningsområden.