Defect-related Si diffusion in GaAs on Si

Preferential diffusion channels of silicon are evidenced in GaAs grown by metalorganic vapor phase epitaxy on Si(100). The density of these diffusion channels is found to be consistent with the measured dislocation density. In addition, combining scanning electron microscopy and x-ray fluorescence it is shown that a large amount of Si emerges at the surface inside small 〈011〉 overgrowth oriented defects (≊1 μm) present at the GaAs/Si surface.