The properties of rare-earth and transition metal oxides of interest for the development of future silicon nanoelectronics will be reviewed. As an introduction, the motivation for using high-k insulators for short channel MOSFET applications is given together with a basic enlightenment on two crucial intrinsic properties of these materials: the dielectric constant, k, and the energy offset value, ?E, in relation to silicon. It will be demonstrated how these quantities govern initial navigation among metallic elements in the periodic table to find future oxide candidates with feasible leakage characteristics. The basic conditions for evaluating the existence of electron states by capacitance versus voltage (C-V) technique at the silicon/insulator interface will be discussed. Finally, a preliminary theory for interpretation of C-V data from metal/oxide/graphene structures is presented.
Conductive carbon thin films are known to be promising candidates for future electrode materials for micro/nano-electronic device applications due to their favourable electrical properties and diversity of formation. In particular, recent enormous interest in graphene, a two-dimensional carbon material, has triggered many broad and comprehensive studies not only on graphene itself, but also on other two-dimensional layered materials such as transition metal dichalcogenides. The introduction of such materials to real electronic device applications can be effectively achieved by making hybrid devices where these materials are combined with conventional semiconductors in device fabrication. Therefore, it is very important to understand and define the electrical characteristics of such hybrid devices thoroughly in the initial stages of research. In this study, two types of hybrid electronic devices such as Schottky barrier diodes and photodiodes have been realised using conductive carbon materials and a semiconducting transition metal dichalcogenide thin film. Material properties have been characterised by a number of techniques and integrated with standard silicon technology. The electrical characteristics of the resulting devices have been investigated using several experimental techniques.
Like no other technology, integrated electronics has changed our daily life and silicon has been the ultimate semiconductor material in micro- and nanoelectronics for more than 50 years. The continuous down-scaling of silicon CMOS devices provides the basis of the tremendous progress in information technology. Without silicon CMOS, the rich multimedia experience we enjoy today when using the internet, mobile phones or tablet PCs would not have been possible. Microelectronics has already completed the transition into nanoelectronics, i.e. state-of-the-art silicon CMOS technologies are utilizing sub-100 nm feature sizes. This continuous top-down miniaturization of silicon-based nanoelectronics is expected to continue into the sub-10 nm range. However, the use of pure silicon based devices will come to an end when CMOS downscaling will soon reach its physical limits. In order to gain performance, new materials with high carrier mobility are required. For the post-silicon CMOS era, hexagonal carbon seems to be a promising alternative to build high performance electronic devices. For example, carbon nanotube field-effect transistors (CNTFETs) can be used as active devices in integrated circuits like CPUs and memory cells as well. More recently, another hexagonal carbon modification became the focus of scientific attention: graphene. Just a few years after the Nobel Prize Award in 2010 for the graphene discovery, graphene-based transistors are emerging as other potential candidates to extend and eventually replace the traditional silicon MOSFET.
After a short-lived appearance in the early 1940s, digital logic computing based on mechanical relays has been recently reevaluated as an emerging solution for solving the CMOS power crisis. Properly designed, an electromechanical switch can indeed present the combined advantages of extremely abrupt DC switching characteristics and essentially zero Off-State current, opening the path towards ultra-low-power logic ICs. During this talk, we will review recent progress in NEMS switch technology and comment on their suitability in terms of area and energy-efficiency depending on transduction mechanism, individual switch configuration as well as circuit design paradigm. We will also evoke challenges and perspectives in terms of contact reliability, device scalability and fundamental energy limits in the case of electrostatically-actuated NEMS.
During the past few years, two-dimensional materials have found a continuously increasing interest in the electronic device community. The first two-dimensional material studied in detail was graphene and many groups worldwide explored graphene as a material for electronic devices, in particular transistors. Meanwhile researchers have extended their work to two-dimensional materials beyond graphene and the number of two-dimensional materials under investigation has literally exploded recently. At present several hundred different two-dimensional materials are known and part of these is considered to be useful for electronic applications. A realistic assessment of the prospects of the two-dimensional materials in electronics, however, is still missing.
