List of Figures

2.1. Thermocouple made of two metal rods.
3.1. Interactions between the subsystems of electrons, holes, and the lattice. While solid lines depict particle exchange, dashed lines denote energy exchange, after [54].
3.2. Hierarchy of simulation approaches. Physically rigorous simulation approaches as well as measurement data are used to parametrize device simulators, which can be based on either quantum mechanical or semi-classical approaches. Device simulation results itself can be used to develop compact models for circuit simulation.
3.3. Illustration of the book-keeping character of Boltzmann's equation for one $\ensuremath {\ensuremath {\mathitbf {r}}}$ - and $\ensuremath {\ensuremath {\mathitbf {p}}}$ -dimension. Possible transitions are a spatial flux of carriers, a change of the carrier's momentum due to an external generic force, and scattering processes, after [73].
3.4. Equi-energy surfaces of the full band structure of silicon within one octant of the first Brillouin zone.
3.5. Fermi-Dirac equilibrium distribution function and Maxwell-Boltzmann approximations at 300K and 1000K.
3.6. Doping dependent Fermi energy with respect to temperature.
3.7. Seebeck coefficients for differently doped p-type silicon samples. Solid lines depict the theoretical models, whereby the decrease for elevated temperatures results from the increased hole concentration in the intrinsic range.
3.8. Seebeck coefficients for differently doped n-type silicon samples.
4.1. Seebeck coefficient, conductivity, thermal conductivity, and figure of merit with respect to free carrier concentration, after [121].
4.2. Thermoelectric figure of merit vs. temperature for several materials used for thermoelectric devices, after [121].
4.3. Thermal conductivity of silicon-germanium alloys with respect to material composition for different temperatures.
4.4. Electron mobility vs. material composition for silicon-germanium alloys for different at room temperature.
4.5. Free carrier concentration as well as figure of merit with respect to material composition for Bi Te , after [175].
4.6. Resistivity as well as thermal conductivity with respect to material composition for Bi Te , after [175].
5.1. Relative static dielectric constant $\ensuremath {\ensuremath {\epsilon }_{\ensuremath {\mathrm {s}}}}$ for PbTe with respect to the temperature.
5.2. Temperature dependence of the specific heat capacity of lead telluride and tin telluride including measurement data and model parameter sets.
5.3. Dependence of the thermal conductivity of lead telluride on the lattice temperature and carrier concentration. While red glyphs depict Bhandari's data [125], the surface denotes the modeled thermal conductivity.
5.4. Material composition dependent lattice and total thermal conductivity of Pb $_{1-x}$ Sn Te at 300K including measurement data and model parameter sets.
5.5. Temperature dependence of the thermoelectric power in n-PbTe for different dopings. The lines depict calculated values while the symbols show according measurement data from [228].
5.6. Temperature dependence of the thermoelectric power in p-PbTe for different dopings. The lines depict calculated values while the symbols show according measurement data from [229].
5.7. Brillouin zone, its first octant, and irreducible wedge with high symmetry points and lines for a face centered cubic lattice.
5.8. Temperature dependence of and transition between direct and indirect band gaps in lead telluride.
5.9. Temperature dependence of and transition between direct and indirect band gaps in lead tin telluride at tin contents of 0.07 and 0.15.
5.10. Temperature dependence of the effective density of states as well as the intrinsic carrier concentration in lead telluride.
5.11. Temperature dependence of the electron mobility in lead telluride for different dopings.
5.12. Doping dependent electron mobility degradation in lead telluride at room temperature.
5.13. Temperature and doping dependent hole mobility in lead telluride.
6.1. Principle configuration of a classical thermoelectric device.
6.2. Voltage and current with respect to the load resistance.
6.3. Electric power output as well as conversion efficiency vs. load resistance for different leg thicknesses.
6.4. Electric current as well as power output vs. load resistance for differently doped devices.
6.5. Voltage as well as conversion efficiency vs. load resistance for differently doped devices.
6.6. Electric power output vs. temperature for differently doped devices.
6.7. Temperature distribution for a non-ideal thermoelectric generator.
6.8. Thermal equivalent network of a thermoelectric device accounting for non-ideal thermal environment.
6.9. Electric power output with respect to the device leg length.
6.10. Electric power density with respect to the device leg length.
6.11. Conversion efficiency with respect to the device leg length.
6.12. Electric power output with respect to the external thermal resistance.
6.13. Current as well as electric power output with respect to the load resistance.
6.14. Thermal heat flux as well as conversion efficiency with respect to the load resistance.
6.15. Electric power output with respect to the material composition in SiGe alloys for several temperatures.
6.16. Conversion efficiency with respect to the material composition in SiGe alloys for several temperatures.
6.17. Temperature dependent Seebeck coefficients for a lead telluride n-type device.
6.18. Temperature dependent power factor for a lead telluride n-type device.
6.19. Electric power output with respect to temperature difference for a lead telluride n-type device.
6.20. Power output with respect to the temperature at the heated end and the ingot length ratio for a stacked lead telluride device.
6.21. Temperature at the ingot interface with respect to the heated end's temperature and the ingot length ratio for a stacked lead telluride device.
6.22. Spatial distribution of thermal conductivity as well as temperature within a stacked lead telluride device.
6.23. Temperature dependent thermoelectric figure of merit for the lowly and highly doped ingots as well as conversion efficiencies for the stacked device and the highly-doped ingot with respect to the heated end's temperature.
6.24. Principle configuration of a large area pn-junction thermoelectric generator.
6.25. Energy relations in large area pn-junction thermoelectric generators.
6.26. Local generation rate at open circuit conditions.
6.27. Electron current density at open circuit conditions.
6.28. Local generation rate at short circuit conditions.
6.29. Electron current density at short circuit conditions.
6.30. Local generation rate at matched load conditions.
6.31. Electron current density at matched load conditions.
6.32. a) Temperature distribution along the pn-junction caused by the thermal conductivities of different Ge-profiles as shown in b). The generation rate shown in c) is exponentially dependent on the temperature, thus the material composition is used to increase the generation rate.
6.33. Power output for pn-junction thermoelectric generators vs. load resistance for several temperature differences and two layer thicknesses.
6.34. Influence of the layer thicknesses on the power output of a pn-junction thermoelectric generator.
6.35. Power output of a thin film thermoelectric generator at different hot end temperatures.
6.36. Spatial distribution of material composition and temperature for a Ge length of 6mm (Structure 1).
6.37. Spatial distribution of material composition and temperature for a Ge length of 10mm (Structure 2).
6.38. Spatial distribution of material composition and temperature for a Ge length of 13mm (Structure 3).
6.39. Heat flux vs. germanium content for different material composition profiles.
6.40. Electric power output vs. germanium content for different material composition profiles.
6.41. Conversion efficiency vs. germanium content for different material composition profiles.

M. Wagner: Simulation of Thermoelectric Devices

			Dissertation Martin Wagner
Previous: Constants Up: Dissertation Martin Wagner Next: List of Tables