Very thin, high Ge content Si0.3Ge0.7 relaxed buffer grown by MBE on SOI(0 0 1) substrate

Growth procedure and excellent properties of very thin 240 nm thick, 95% relaxed, high Ge content Si0.3Ge0.7 buffer grown on SOI(0 0 1) substrate are demonstrated. All epilayers of the newly developed Si0.3Ge0.7/SOI(0 0 1) variable-temperature virtual substrate were grown in a single process by solid-source molecular beam epitaxy. Surface analysis of grown samples revealed smooth, cross-hatch free surface with low root mean square surface roughness of 0.9 nm and low threading dislocations density of 5×104 cm−2.