There is a new way to design computer chips and electronic circuitry for extreme environments: make them out of diamond. A team of electrical engineers at Vanderbilt University has developed all the basic components needed to create microelectronic devices out of thin films of nanodiamond. They have created diamond versions of transistors and, most recently, logical gates, which are a key element in computers.
“Diamond-based devices have the potential to operate at higher speeds and require less power than silicon-based devices,” Research Professor of Electrical Engineering Jimmy Davidson said. “Diamond is the most inert material known, so our devices are largely immune to radiation damage and can operate at much higher temperatures than those made from silicon.” Their design of a logical gate is described in the journal Electronics Letters.
Scientists have made a breakthrough toward creating nanocircuitry on graphene, widely regarded as the most promising candidate to replace silicon as the building block of transistors. They have devised a simple and quick one-step process based on thermochemical nanolithography (TCNL) for creating nanowires, tuning the electronic properties of reduced graphene oxide on the nanoscale and thereby allowing it to switch from being an insulating material to a conducting material.
The technique works with multiple forms of graphene and is poised to become an important finding for the development of graphene electronics. The research is published in the Science journal. Scientists who work with nanocircuits are enthusiastic about graphene because electrons meet with less resistance when they travel along graphene compared to silicon and because today’s silicon transistors are nearly as small as allowed by the laws of physics. Graphene also has the edge due to its thickness – it’s a carbon sheet that is a single atom thick. While graphene nanoelectronics could be faster and consume less power than silicon, no one knew how to produce graphene nanostructures on such a reproducible or scalable method. That is until now.
The recent emergence of graphene has generated a world-wide – and highly competitive – scientific enthusiasm, due to the extraordinary properties which are expected from graphene-based nano-objects and their derivatives. Its structural and chemical simplicity makes graphene a very convenient systems for fundamental research and for the development of nano-scale sciences. On the other hand, the numerous variations of the graphene based nano-objects allow a unique variability of properties (transport, mechanical, optical, chemical…) and an unusually high number of potential applications, spanning energy, nanoelectronics, or chemical industry. Graphene is also ideal for chemists who can modify its properties by functionalisation, grafting, adsorption and doping. Investigating graphene clearly requires the involvement of scientists in areas related to physics, chemistry, and materials sciences.
This growing interest, triggered by the numerous potential applications of graphene in future nanotechnology, motivates the creation of an interdisciplinary school on graphene. The school is aimed at PhD students, post-doctoral and young researchers in the first instance. The School is taking place in Cargèse, France from October 12 to October 22, 2010 at the Institut d’Etudes Scientifiques de Cargèse.
In a groundbreaking series of experiments, scientists in the United States managed to develop a new method of analyzing how graphene sheets are stacked on top of each other. The technique is also suitable for determining which areas of the compound are subjected to most strain, when the material is placed inside more complex structures. All of this can be inferred using moire patterns, which are interference patterns that appear at an atomic scale, when two layers of atoms are placed on top of each other imperfectly, as in slightly askew (image courtesy of NIST).
The research team that conducted the new investigation features physicists from the US National Institutes of Standards and Technology (NIST) and the Georgia Institute of Technology (Georgia Tech). The experts say that the moire patterns can also be used on multiple grids or atom arrays, not only on two. They add that using “atomic moire interferometry” can also help scientists determine the rotational orientation of the graphene sheets used in a variety of technological applications. Their work is published in the Physical Review B journal.
Understanding energy dissipation and transport in nanoscale structures is of great importance for the design of energy-efficient circuits and energy-conversion systems. This is also a rich domain for fundamental discoveries at the intersection of electron, lattice (phonon), and optical (photon) interactions. A review article published in NanoResearch presents the recent progress in understanding and manipulation of energy dissipation and transport in nanoscale solid-state structures.
Some of the greatest challenges of modern society are related to energy consumption, dissipation, and waste. Among these, present and future technologies based on nanoscale materials and devices hold great potential for improved energy conservation, conversion, or harvesting. A prominent example is that of integrated electronics, where power dissipation issues have recently become one of its greatest challenges. Power dissipation limits the performance of electronics from handheld devices (~10–3 W) to massive data centres (~109 W), all primarily based on silicon micro/nanotechnology.