Effective compliant substrate for low-dislocation relaxed SiGe growth Available to Purchase

An effective compliant substrate was fabricated for the growth of high-quality relaxed SiGe templates, by synthesizing a 20% $B2O3$ concentration borosilicate glass (BSG) in the silicon on insulator wafers. Substrates with 5%, 10%, and 20% $B2O3$ were used for 150 nm $Si0.75Ge0.25$ epitaxy. Double-axis x-ray diffraction measurements determined the relaxation and composition of the $Si1−xGex$ layers. Cross-sectional transmission electron microscopy was used to observe the lattice of the SiGe epilayer and the Si substrate, dislocation density, and distribution. Raman spectroscopy was combined with step etch to study the samples. The strain sharing effect of the 20% BSG substrate was demonstrated. Thus, we concluded that this compliant substrate is a highly promising candidate for the growth of low-dislocation relaxed SiGe layers.