We investigated alpha-Fe2O3 (0001) film growth on alpha-Al2O3 (0001) using a laboratory-built dc faced magnetron sputtering system with x-ray diffraction, x-ray reflectivity, and atomic force microscopy (AFM). The films were deposited from iron targets at a growth rate of similar to 6.3 nm/min in an ambient argon and oxygen mixture. The structural properties and quality of the alpha-Fe2O3 thin films were characterized using high-resolution synchrotron x-ray scattering. Films thinner than 16 nm were to be found highly strained due to the large lattice mismatch between film and substrate of 5.8%. This strain was found to decrease as the film thickness increased, and most of the strain was released through surface modulation once the film thickness reached 20 nm. The epitaxial relationships were found to be alpha-Fe2O3 [0001]vertical bar vertical bar alpha-Al2O3 [0001] in the out-of-plane direction. That the film and substrate display the in-plane alignment anticipated for the epitaxy of isomorphous materials was established by verifying that the [11 (2) over bar0] directions of film and substrate were coincident. X-ray reflectivity and AFM were used to show that layer-by-layer growth of alpha-Fe2O3 (0001) occurs up to a thickness of 11 nm despite the large lattice mismatch. (c) 2005 American Vacuum Society.