Temperature dependence of surface roughening during homoepitaxial growth on Cu(001) - art. no. 125427

X-ray scattering has been used to study the roughening of the Cu(001) surfa ce during homoepitaxial growth. as a function of temperature. Between 370 a nd 160 K. the mean-square roughness sigma (2), obtained from specular refle ctivity data, was found to increase as a power law sigma (2)=Theta (2 beta) for coverages Theta, ranging from 3 to 96 ML. The roughening exponent beta was observed to depend on the temperature of the substrate: it monotonical ly increases with decreasing temperature from beta approximate to 1/3 at T= 370 K to beta approximate to 1/2, at T = 200 K. At 110 K a smoother growth re-enters in the presence of a large vacancy concentration in the deposite d film.