J. Vac. Sci. Technol. B 12(3) 1789-1792

Scanning tunneling microscopy study of the growth of Cr/Fe(001):
Correlation with exchange coupling of magnetic layers

Joseph A. Stroscio, D. T. Pierce, J. Unguris and R. J. Celotta

Scanning tunneling microscopy (STM) and reflection high-energy electron 
diffraction (RHEED) were used to study epitaxial growth of Cr on Fe(001) 
whiskers as a function of the Fe whisker temperature during growth. The 
STM images give real space views of the morphology of Cr growth, which can 
be correlated with the nature of the RHEED intensity oscillations. Layer 
by layer growth is found for Cr deposition on an Fe(001) surface at 300 
oC, and very rough growth, limited by diffusion kinetics is observed at 
lower temperatures. The variation in the interlayer exchange coupling in 
Fe/Cr/Fe sandwiches as a function of the thickness of the Cr interlayer, 
which has been found to depend strongly on the growth temperature of the 
Cr interlayer, can be explained by the thickness fluctuations determined 
from the STM measurements of Cr films grown at different temperatures.