Online at stacks.iop.org/JPhysCM/17/V1Device miniaturization, speed of operation, and lower power demands are all responses to consumer needs. These driving forces are at the origin of the spectacular development of the microelectronic Si-based technology, characterized by an exponential scaling behaviour which has been persisting for over four decades [1].During this extended period of time, this technology has almost exclusively relied on the extremely convenient physical properties of the Si-SiO 2 interface, the interface between crystalline silicon and its thermal oxide [2,3]. In the present generation, gate-oxide layers are grown with thicknesses around 20 Å and with interfaces which are nearly abrupt at the atomic scale. Furthermore, specific nitrogen concentration profiles are engineered across the thin film to control the diffusion of dopants [3]. Further scaling of the Si-SiO 2 system is now prevented because of fundamental limits associated to leakage currents and reliability concerns [1]. Overcoming these limitations will require the use of alternative gate-oxide materials, of higher dielectric constant (high-κ materials) than SiO 2 [4]. The ability to control both the atomic structure and composition of these new oxide layers is emerging as one of the major challenges for the next generation of Si-based electronic devices. Controlling the atomic properties of thin dielectric films is currently becoming a relevant issue also for the development of oxide-based devices with other functional properties. Recent reports on surprising magnetic properties in oxides, including room-temperature ferromagnetism with giant magnetic moments, offer new perspectives for the development of magneto-optic and spin-electronic devices that could operate in ambient conditions [5][6][7]. The fundamental nature of the dielectric response in thin-film ferroelectric perovskite oxides is currently being addressed in view of identifying key materials for the development of novel random access memory technology [8]. Other relevant developments include the fabrication of field-effect transistors based on perovskite oxides as active elements [9] and atomically engineered hetero-oxide interfaces showing unusual charge states with surprisingly high carrier mobilities [10]. In all these developments, sophisticated oxide films play the central role.