Growth-rate-dependent laterally graded SiGe profiles on insulator by cooling-rate controlled rapid-melting-growth

Abstract

Laterally graded SiGe-on-insulator is the key-structure for next-generation Si-technology, which enables advanced device-arrays with various energy-band-gaps as well as 2-dimensional integration of functional-materials with various lattice-constants. Segregation kinetics in rapid-melting growth of SiGe stripes are investigated in wide ranges of stripe-lengths (10–500 μm) and cooling-rates (10–19 °C/s). Universal laterally graded SiGe-profiles obeying Scheil-equation are obtained for all samples with low cooling-rate (10 °C/s), which enables robust designing of lateral-SiGe-profiles. For samples with high cooling-rates and long stripe-lengths, anomalous two-step-falling profiles are obtained. Dynamical analysis considering the growth-rate-effects enables comprehensive understanding of such phenomena. This provides the unique tool to achieve modulated lateral-SiGe-profiles beyond Scheil equation.

Melting and homogeneity in germanium–silicon alloys and a modified micro-manufactured assembly for stable high pressure and temperature measurements

“…The presence of two significantly different compositions demonstrates segregation ease at the pressures of this experiment for the Ge-rich sample. Figure 4(b) conversely, of a 1:3 Ge:Si starting mix including a pattern in the melt and upon recovery indicates only marginal segregation, indicating that pressure may assist in homogeneous alloy formation, supported also by the lower segregation coefficient [11] associated with the Si-rich section of the phase diagram, as noted in the introduction. A very detailed, evolution of the development of this Si-rich alloy from the component elements at high temperature, at pressure, all the way through melting is shown in Figure 4(c) of a 3:1 Ge:Si starting mix to 7.4 GPa, 2 GPa higher than our other Ge-rich experiment (Figure 4(a)), indicates a much diminished segregation of a Ge-rich sample which may be consistent with decreased atomic mobility in the melt in targeted higher pressure regions, [12] but compositional variation and further experiments need to be considered for this.…”

Ciclo térmico y soldabilidad de las aleaciones de aluminio

“…Este factor se obtiene mediante la pendiente de la línea de equilibrio líquidus hacia la línea de equilibrio del solidus. Mediante la ecuación de Scheil (Matsumura et al, 2012;Stoicanescu et al, 2013) se aproxima la fracción en peso eutéctico gene rado f. Donde C o es la composición de la aleación y C E es la composición eutéctica. Los valores del coeficiente de partición y fracción en peso en la Tabla 2.…”

Silicon-germanium composition engineering for next generation multilayer devices and systems

“…An alternative technique known as rapid melt growth (RMG) offers the potential for formation of localized single crystal, defect free layers at a low cost using only a single Ge deposition step and a single anneal step. However, until now this technique has resulted in a graded SiGe composition [5,6], rendering it unsuitable for most devices and applications. Here, for the first time we report a method of engineering the SiGe composition to a near constant value with the use of tailored tree-like structures, which will revolutionise deployment of SiGe in circuit architectures.…”