DEPENDENCE OF ERAS CLUSTERING AND ER SEGREGATION IN ERAS/GAAS HETEROSTRUCTURES ON GROWTH TEMPERATURE

The effect of growth temperature on the growth properties of ErAs/GaAs heterostructures grown by low-temperature migration-enhanced epitaxy and molecular beam epitaxy is investigated in detail using transmission electron microscopy, double-crystal X-ray diffraction and secondary ion mass spectroscopy. Our results demonstrate that the formation of ErAs clusters at the ErAs/GaAs interface occurs even at very low growth temperatures (320-degrees-C). Moreover, we clearly observe that the size of the clusters drastically increases and Er segregation takes place when the growth temperature is increased. All our characterization results suggest that when the samples are grown by migration-enhanced epitaxy at 320-degrees-C, these problems can be limited, leading to an enhancement of crystal quality.