HIGH-RESOLUTION ELECTRON-MICROSCOPY OF CRYSTALLINE-AMORPHOUS INTERFACE - AN INDICATION TO EDEN AGGREGATE

The interface between crystalline and amorphous phases in partially crystallized Al:Ge amorphous thin films was examined by high resolution electron microscopy and by nanoprobe analysis. The interface shows no smoothness at any scale down to the atomic scale. No gradient of concentration was found in the amorphous phase even at irregularities, but pockets of amorphous phase were found in the crystalline scale. These results indicate that no long range atomic mobility exists during crystallization, thus no diffusion in the amorphous phase nor surface diffusion in the crystal interface. The Eden model for growth is well suited to describe the interface morphology.