Liquid phase diffusion growth of SiGe single crystals under magnetic fields

The manuscript presents the results of a combined experimental and modeling study on the Liquid Phase Diffusion (LPD) growth of single crystal SixGe1-x on Germanium with and with the application of magnetic fields. Although the LPD process is mainly diffusion driven through out the growth period, strong natural thermosolutal convection occurs in the first five hours of growth, and the growth interface is concave to the melt. Applied rotating and static magnetic fields were considered to examine the growth and silicon dissolution processes in the LPD system. Results show that the application of a combined applied magnetic is beneficial

Optical properties of SiGe single crystals grown by liquid phase diffusion

In this article, we present measurements for the pseudo-optical functions of germanium-rich SixGe1-x (0.000<x<0.100) single-crystals(grown by Liquid Phase Diffusion; LPD) using spectroscopic ellipsometry and photo reflectance techniques in the energy range of 1.72–3.20 eV. The E1 interband transition energies are obtained from numerically differentiated optical spectra for various crystal compositions. It was shown that the values of E1 interband transition energy determined by both the ellipsometric and photo reflectance measurements for germanium-rich SixGe1-x single-crystals are in agreement with those of bulk SiGe crystals reported in the literature[21–24].The interband transition energies are found to be in the range of 2.100 and 2.215 eV for the composition values of 0.000<x0.100. The surface morphology of the crystals assayed via atomic force microscopy shows fibrous surfaces with the average grain size of 250 nm. The measured root-mean-square (rms) roughness and maximum height are in the range of 3.78–5.40 and 32.42–67.84 nm, respectively, with increasing germanium composition

Growth of bulk SiGe single crystals by liquid phase diffusion method: experimental and computational aspects

SiGe is an emerging semiconductor material with many promising applications in high-speed micro electronics and thermo-photovoltaics. In light of significant differences in physical properties of constituent elements, it is still a challenge to grow bulk SiGe single crystals with uniform composition and low defect density. Thus, it is essential to scrutinize the solidification behaviour of SiGe system. Hence, this book presents a combined experimental and modelling study for the growth of SiGe single crystals by a new solution growth process called Liquid Phase Diffusion (LPD). Following a brief introduction of the subject, the crystal structure, phase diagram, growth techniques used for producing SiGe single crystals and their place in the overall scheme of SiGe alloy systems are presented. The development of a macroscopic mixture model is presented to model the LPD growth system. The LPD growth system is examined using two- and three-dimensional transient simulations. The design, construction, and testing of the LPD growth system are presented along with the experimental results and characterization of grown crystals

Energy intensities for Canada

The gross domestic product (GDP) measures the value of goods and services produced in a country in one year. There is a close relationship between the GDP and energy supply (and consumption). This relationship is a good indication of the level of economic development of a country. The GDP per capita is often used to measure the living standard of a country. Measures of the total energy use are useful for addressing energy intensity issues. Energy use is a numerator in determinating energy intensities. A commonly used and frequently quoted measure of energy use is the ratio of energy expenditure to GDP. Two types of energy intensities, namely TPES/GDP and TFC/GDP, are useful tools in making comparisons for both energy and GDP projections for countries. In this article we present evaluations and future projections for energy resources and energy intensities for Canada. The total primary energy supply (TPES) and total final energy consumption (TFEC), and energy intensities for supply and consumption are analyzed. The energy data are presented and analyses of the differences in energy and GDP ratios are carried out at an aggregate level by examining differences in factors affecting the energy intensities. In order to provide accurate projections for the future, new correlations were developed between the GDP, TPES, TFEC, TPES/GDP, TFEC/GDP, and population of Canada.

Thermal diffusivities of geometrical objects subjected to cooling

This paper presents a new mathematical model for determining thermal diffusivities of very common solid geometrical objects such as an infinite slab, infinite cylinder, or sphere cooled in a medium. In practice the model will be implemented by using the center temperature measurements of these solid objects, and then the cooling coefficients will be obtained. The cooling coefficient, which is the most important process parameter, has a strong effect on the thermal diffusivity. An illustrative example of the use of the model is presented. In addition, new characteristic equations of the transient heat transfers for these geometrical objects were developed. The results of this study show that the present model can be considered as a simple and efficient tool for determining thermal diffusivities of geometrical objects subjected to cooling.

TED-AJ03-107 NUMERICAL STUDY OF THERMAL AND SOLUTAL MARANGONI CONVECTION IN A 3-DIMENSIONAL FLOATING FULL-ZONE LIQUID BRIDGE

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