Real‐time observation of surface morphology at nanometer scale using x‐ray specular reflection

The changes of surface morphology at nanometer scale during metal–organic vapour‐phase epitaxial growth of indium phosphide have been investigated by using x‐ray specular reflection at grazing incidence. At the low growth temperature of 400°C, large decreases of x‐ray beam intensity were observed, suggesting the formation of nanometer‐sized nuclei. At a higher growth temperature of 500°C, oscillations estimated to by layer‐by‐layer growth were observed, and roughness changes obtained from these oscillations were <0.01 nm, suggesting small‐island formation on the terrace or step‐edge fluctuation during the growth. Additionally, reflectivity increases at a growth temperature of 550°C were observed. Considering the reflectivity dependence on t‐butylphosphine flow at 400°C, the change of reflectivity at 550°C is explained by the existence of phosphorus layers before the growth. Copyright © 2003 John Wiley & Sons, Ltd.