Initial nanoheteroepitaxial growth of GaAs on Si(100) by OMVPE

Initial growth studies of GaAs on an array of Si islands nanostructured on (100) oriented silicon-on-insulator substrates show that growth occurs thro ugh a mixture of selective-area and 3D growth modes. An optimum initiation growth temperature must tune the growth conditions to the geometry of the s eed array so that selective-area control is maintained while defect density is minimized. The optimum temperature for a square array of Si islands, 50 0 nm in pitch, and 100 nm to 280 nm in diameter, is similar to 600 degreesC . This temperature yields single-crystal nucleation on each Si island while maintaining selective-area growth mode control. Transmission electron micr oscope (TEM) analysis of optimized and nonoptimized grown GaAs/Si heterostr uctures show that they accommodate 0.4-0.7% strain. Further reduction in st acking-fault defects attributed to side wall growth may be possible through masking of side wall or annealing.