Academics and large corporations all over the world are busy pouring money into nanotechnology research. Finding new ways to build smaller, more powerful CPUs; low-power, flexible computer displays and touchscreens; and longer-life device batteries are just some of the applications high on their agendas.
Not all nanotechnology implementations will have an impact on IT, however – arguably the majority of applications are being designed for use in the field of medical science, biofuel production, solar energy, pharmaceuticals and even paper manufacturing, among others.
What is nanotechnology?
Nanotechnology is the logical successor to microtechnology – a term commonly used to define miniature circuits around a single micrometre (one millionth of a metre) in size, which have been used to form part of micro-electromechanical systems (MEMS).
Perhaps the best example of MEMS usage in IT is in the formation of integrated circuits (ICs) that consist of tiny processors and passive components manufactured within a thin substrate of semiconductor material. Typical material examples include silicon and metals such as gold, nickel and titanium, with various etching processes used to put burn patterns on the chips, and which are already found in many forms of electronic equipment today.
MEMs are also used in optical switching equipment and digital cameras, as well as accelerometer chips in small electronic devices such as smartphones, handheld PCs and MP3 players. They are also used in PC hard drives to stabilise the read head to prevent disk damage and data loss.
Nanotechnology takes microtechnology further by miniaturising technology either to an atomic or molecular scale, or to structures fewer than 100 nanometres in size (to put things in perspective, a nanometre is roughly equivalent to a billionth of a metre).
One idea is that molecular structures can be used to replace electronic components, producing switches and ICs only a few atoms wide, which can be used in electronic devices to greatly reduce their size, without affecting speed or performance.
In other words, smaller, faster computers, with larger memories and more powerful CPUs than silicon-based chips currently allow, using techniques such as soft lithography to produce cheap and effective nanoscale circuits based on alternative materials.
Carbon nanotubes in CPUs
Much of the work being done with nanotechnology revolves around semiconductors, which is the reason why many companies are putting considerable financial resources into researching a specific area of nanotechnology called carbon nanotubes.
These are made when carbon atoms form hollow, open-ended cylinders that have diameters between 0.4nm and 1.8nm, and vary in length up to several hundred nanometres depending on how they are made. Electrons flow through these nanotubes 10 times faster than they do through silicon circuits found in most CPUs, while they can carry up to 100 times the current and dissipate up to 20 times the heat.
Intel obtained a US patent for its carbon nanotube-coated capacitor electrodes and their manufacturing method, and the resultant capacitors, intended to provide power to electronic devices such as desktop PCs, servers, laptops, handhelds, gaming devices and telephones.
Nanowires in memory
Intel, HP, IBM and others are also exploring semiconductor nanowires for use in CMOS memory – up to 100 bits of data could be stored on a single nanowire, says the company, delivering between 10 and 100 times more data than other solid-state memory such as Flash, at lower cost.
To this end, IBM researchers recently announced the creation of a ring oscillator out of field-effect transistors based on 3nm-diameter nanowires, demonstrating that engineers can build a working circuit from transistors at much smaller channel lengths than today’s devices.
Researchers at Samsung Electronics had previous demonstrated a similar circuit based on 13nm nanowires, and HP has promised a 4.5nm wire by next year – but it is expected to be several years before either version of the technology makes it into memory chips.
HP is also experimenting with a new system architecture that allows multiple layers of memory to be stacked 3D-fashion. Details remain vague to date, and nor is it clear if the “nanostore” operates on a nanoscale, in the same way that Apple’s Nano doesn’t. But it is intended as a stack of processor cores connected to HP’s non-volatile memristor cores in datacentre servers, meaning much of the processing is performed within memory rather than CPU, resulting in up to a tenfold increase in performance, said HP.
Carbon nanotubes can also be used as either conducting or semiconducting material for use in data storage, while scanning probe microscopes may eventually be used as a tool for data transfer.
IBM’s millipede storage system, for example, uses an array of atomic force microscope (AFM) tips to make indentations in materials such as polymer and read them similar to the way that lasers read CDs, but at considerably smaller scale and much higher density of information.
Hitachi Maxell has partnered with the Institute of Technology in Tokyo to create new tape storage technology which would allow products to reach capacity of more than 50TB, using what it calls the facing targets sputtering method, an ultra-thin nano-structured magnetic film (magnetic particles are fewer than 10 nanometres), allowing it to fit more information into a much smaller area and raising the number of bits that can be stored.