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.