Metal-metal epitaxy on silicon: Cu/Ni/Cu ultrathin films on 7 x 7-Si(111)

Cu/Ti/Cu heterostructures have been in situ deposited on the 7x7 reconstruc ted Si(111) surface. A number of complementary techniques, such as in situ low-energy, medium-energy and Kikuchi electron diffraction and ex situ N-ra y diffraction, were used in order to characterise the growth process and th e structural properties of the films. It is found that the growth mode of m etallic films is characterised by the presence of twinned islands induced b y the 7 x 7 reconstruction of the Si(111) substrate. This work can stimulat e further application of the metal-metal epitaxy on silicon to grow high qu ality ultrathin magnetic films to be integrated in microelectronic devices. (C) 2000 Elsevier Science B.V. All rights reserved.