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The article reports that Japanese researchers have created a liquid silicon that can be inkjet printed to create thin-film transistors (TFTs) with higher mobilities than organic semiconductors. The work could lead to a low cost, scaleable process for depositing TFTs for large area displays, without the complex vacuum conditions and lithography steps currently required. The process uses a silicon-containing compound called cyclopentasilane (CPS) dissolved in a mixture of organic solvents. The CPS is partially polymerized using UV light, and then baked to remove some of the hydrogen. The low hydrogen content and high disorder of the resulting film means carrier mobilities are significantly lower than conventionally deposited amorphous silicon.

This article reports that a national facility for high technology silicon process development, seen by industry and academia as essential for Great Britain's competitiveness in mainstream semiconductors, won't be funded. At least not through the British Office of Science and Technology's Large Facilities budget, the contenders for which are due to be shortlisted in the next few weeks. Apart from a general lack of faith in government committees and processes, reasons for the scepticism include comments last week from John Wand, head of Materials at the Engineering and Physical Sciences Research Council, that the council will have a better idea of British nanotechnology capabilities when it completes a review in October 2006. The Budget also raised the possibility that in future, projects such as the mini-fabrication will struggle to find support, since it proposed the formation of a dedicated Large Facilities Research Council.

The article presents information on the demand of silicon mini-fab in the Great Britain. The mini-fab is being considered by the British Office of Science and Technology part of its Large Facilities Roadmap. Sir Alec Broers, president of the Royal Academy of Engineering said that the future of silicon is very bright in Great Britain. He says that silicon is what everything is built on.

The article reports on workable optical memory. Professor Thomas Krauss, a member of Great Britain's Ultrafast Photonics Collaboration at the University of St. Andrews in Scotland, said that he is working on structures that should be able to store a few bits, and clearly this can be pushed further. At the same time, novel architectures may emerge that can operate with storing fewer bits than needed today, and eventually the two may merge. Krauss has recently been working with colleagues at the University of Twente in the Netherlands on techniques to image the behaviour of light inside specially patterned silicon-on-insulator waveguides directly. Krauss and his colleagues have devised new structures, but as yet it is too soon to say whether they have solved issues such as multiple modes of slow light being excited in the material.

The article reports that Freescale Semiconductor Inc. has announced a 24Mbit version of its silicon nanocrystal memory, first detailed in a 4Mbit device two years ago. The company is touting the dense, low-voltage technology as a replacement for flash. The memory replaces the floating gate found in flash with a series of isolated silicon dots. The charge is stored on these dots, and can only be lost from those which align with defects in the tunnel oxide. As a result a thinner tunnel oxide can be used, which enables lowervoltage operation without impairing reliability. It also enables two bit-per-cell operation.

The article reports that researchers in the U.S. have taken another step towards an electrically pumped silicon laser after demonstrating all the required behavior from a piece of bulk silicon with a nanoscale pattern etched into it. Among the features were optical gain, a threshold behavior, and modes consistent with a laser cavity. The device operated at cryogenic temperatures, and with very low efficiencies, but the scientists, led by Jimmy Xu at Brown University in Providence, Rhode Island, said its performance was similar to that of early solid state lasers and offered room for improvement. Although the laser was optically pumped, its mode of action is such that electrical pumping should be possible. This compares with another silicon laser, announced by Intel at the beginning of the year, which relies on a non-linear optical effect and so could not be electrically pumped on a silicon chip.

The article reports that semiconductor IP supplier Silicon Hive, a spin out from Philips Electronics NV, has added support for multi-core designs to its hardware and software development systems for its family of programmable processors. The company's Hive Flex application-specific instruction-set processors are grouped into the Avispa family of low power designs and the Moustique family, which emphasizes low silicon area. The devices are designed to target specific applications such as communications or media processing. The version 2.0 software integrates the company's HiveCC ANSI-C compiler, a simulator/emulator and a debugger.

This article reports that International Business Machines Corp. (IBM) has developed a silicon chip that can slow light down on demand. Although researchers have been able to slow light dramatically using gases of cold atoms for some years, repeating the effect in a device using standard silicon processes is a first. The company said that the work is an important step towards creating small, integrable photonic components for things like optical delay lines, optical buffers, and eventually an optical memory. The IBM device consists of a strip waveguide joined to a photonic crystal waveguide on which two metallic contacts are deposited.

This article reports that a fire at the Southampton, England-based University of Southampton has destroyed facilities belonging to two prestigious research groups and the silicon technology developer Innos. The cost of rebuilding and re-equipping the labs and cleanrooms affected is estimated at £50. The research groups affected are in the Optoelectronics Research Centre (ORC), and the School of Electronics and Computer Science. Research in the ORC has been spun out to form nine companies, among them SPI Lasers and Mesophotonics.

This article reports that the U.S. researchers have developed a high-speed optical modulator that can be integrated with existing silicon process technology. The work, which solves a problem typically associated with such devices made using Group IV materials, could lead to optical components operating at 100GHz. Optoelectronic components are typically built from III-V semiconductor systems such as GaAs and InP, which have a direct bandgap and display a strong quantum-confined Stark effect. The scientists, at Stanford University and HP Labs in California, used this to create a compact electro-optical modulator.

This article reports that the world of fancy watches has begun borrowing from the semiconductor industry. Swiss firm Patek Philippe SA has replaced a key metal wheel with one micromachined from silicon. The company worked with the Institute of Microelectronics at the University of Neuchatel, Switzerland, to come up with the part, which is made in one photolithographic step, compared to 30 for a metal version. Patek Philippe said there are sound engineering reasons for making the change. Unlike metal, the silicon version needs no lubrication.

The article reports that Silicon Labs has released two families of frequency control products that use its digital signal phase locked loop technology to provide reliable, low jitter frequency generation up to 1.4GHz. Mike Petrowski, director of networking products at Silicon Labs, said that there are lots of people making XOs and VCXOs, either using SAWs or high frequency fundamental inverted mesa crystals. Because creating a high frequency resonator using either of these approaches is not straightforward, and suppliers do not maintain large inventories, customers are used to long lead times and relatively poor reliability. The Silicon Labs Si530 and Si550 XOs and VCXOs are based on a single fixed, low frequency crystal which the clock synthesis IC uses to synthesize any frequency over a range from 10MHz to 1.4GHz.

This article reports on a novel single-mode optical fibre that offers strong non-linearity in the mid-IR region of the EM spectrum. It has been developed by researchers at the University of Southampton. The so-called "holey" fibre is made by extruding a preform of a sodium-zinc-tellurite glass, rather than by carefully stacking lots of capillaries together and drawing those out into a fibre, the technique typically used with conventional silica glasses. The production technique involves drawing a preform for the core structure (which will serve to introduce the holes) into a rod with an outer diameter of 1.2mm.

The article reports that the company E2v Technologies has won the contract to supply 1.5Gpixel worth of charge coupled devices (CCD) image sensors for the European Space Agency's GAIA space mission, scheduled to fly in 2011. The company's CCDs are in single crystal silicon with a polysilicon/metal/dielectric fab process. The company will produce 170 chips, each 4500 lines x 1966 rows wide. The GAIA contract is worth 9.6m pounds over the coming three years and should make use of the six-inch line E2v.

This article presents information on the statistical approach to manage power in 65nm designs. Researchers argue that deterministic static analysis, assigning fixed values for IR drop, leakage currents and so on according to worst-case evaluations does not consider statistical variations in the underlying silicon. Using a statistical model like Monte Carlo type techniques is to come up with a normal distribution around a chosen performance target. During a panel session at DAC last week Andrew Yang, CEO of Apache Design Solutions, spoke about the need to think of power in terms of "power integrity".

This article reports that the graphic detail of single molecule transistor shows dangling bonds. When attached to a silicon surface, the researchers found that the conductivity through the molecule, which is a derivative of the aromatic organic compound styrene, was affected by how close it was to a so-called dangling bond in the silicon. The effect meant that at a bias of -1.6V between the surface and an atomic force microscope tip, only the molecules nearest the dangling bond stood up away from the surface towards the tip.

This article focuses on Great Britain success in precisely controlling strain in semiconductor wafers that is of key importance to device function. The devices were built on a strained-Si-SiGe virtual substrate on a silicon wafer. And AdvanceSis, the University of Warwick spin out, is close to announcing results of its work on strained silicon. The company has completed installation of a £ 2m chemical vapour deposition reactor, which is now producing wafers. AdvanceSis is developing IP for virtual substrates made using SiGe and SiGe:C which are used to control the strain and therefore carrier mobility in a silicon layer grown on top.

This article focuses on a novel process for depositing precious metals on substrates such as glass and silicon by University of Saint Andrews. Ceimig's patented, solvent-free technique uses only three steps to write metal tracks, up to four stages less than current etching processes. Unexposed material is washed off using a nitrogen gas flow at 80° Celcius. The underlying chemistry is also being used to create a simple, robust CO2 sensor, a device, James Thomson said is not currently available and for which there is a need there are moves to replace CFC coolants in car air conditioning systems with liquefied CO2.

This article presents information related to N-Channel Mosfets. Researchers in Great Britain have dramatically enhanced the performance of n-channel Mosfets processed at CMOS-compatible temperatures. On-state drain current and maximum transconductance in the devices, which were built on a strained-Si-SiGe virtual substrate on a silicon wafer, were increased by up to 220 per cent over pure silicon control transistors. The researchers, at Southampton silicon technology specialist Innos and the University of Newcastle, varied the composition of the SiGe alloy and obtained best performance from a device with a 300nm channel length built on a relaxed S0.

The article reports on initiation of a project by Bell Labs to use its nanograss nanostructured surfaces in a liquid cooling system for chips. Although currently using multiple cores is seen as the most persuasive strategy for reducing the heat output, Bell Labs expects that eventually liquid cooling will be a requirement. A droplet of fluid resting on a nanograss surface doesn't seep down between the pillars, reducing the contact area by up to a factor of 50 compared with planar silicon. Viscous drag is thus dramatically reduced, and coolants should be able to flow much more easily through nanograss-lined channels.

The article reports that the increase in leakage current and its impact on static power dissipation on moving from 0.13μm to 90nm processes is well documented. A further technique is to enable the use of mixed threshold voltages and tools from the major EDA suppliers now allow designers to do this in an automated fashion. The method is well established and can significantly reduce static power while maintaining speed and area. The approach taken by Virage Logic Corp.'s fellow Californian IP vendor, Virtual Silicon, rests on a proprietary technology to enable gate biasing in individual cells.

This article reports that one way of manipulating matter on the nanometre scale to build electronic devices is to let it organise itself into predictable patterns, so-called "bottom-up," manufacturing. At the University of Nottingham, professor Neil Champness and colleagues are developing the controllability of a molecular self-assembly technique they first reported last year. A mixture of two differently shaped organic molecules arrange themselves into a hexagonal network on a silver-terminated silicon surface. The driving force for the organisation was intermolecular hydrogen bonding.

The article focuses on a new £1.2 million, four year research project involving the universities of the West of England (UWE), Leeds and Sussex. "For fifty years AI has been trying to build systems that have got complicated behaviour, with some success," said Larry Bull from UWE, who will lead the project. "But given this complex behaviour seems to be easy in the natural world, networks of neurons and chemical systems, why don't we try to build AI systems out of that stuff, rather than try to write clever programmes?" The first step will be to build simple logic circuits that reproducibly perform AND or XOR operations and so on. With those systems in place, the focus will shift to tackling problems silicon systems find difficult, for example vision-based tasks, or tasks in which there is a non-linear relationship between the inputs.

In an attempt to create a silicon-compatible high-temperature terahertz laser, researchers at Cambridge University have demonstrated population inversion in a SiGe quantum cascade device. Although they have not yet succeeded in obtaining laser action from the electrically-pumped device, group leader Dr Douglas Paul said its temperature performance suggests 300K is feasible. In a quantum cascade laser charge carriers injected into a stack of layered materials trickle down a series of energy levels , emitting energy as light— or terahertz radiation— as they do. The Cambridge group is aiming at obtaining emission at 3THz, using a QCL made from 1,200 layers of SiGe of different stoichiometries.

International Business Machines researchers have developed a CMOS-compatible germanium on silicon-on-insulator (SOI) photodetector that they claim will allow very high speed optical interconnects to be integrated on-chip. The device operates at 1V and has an optical frequency response of 29GHz, which in principle makes it good for 50Gbit/s signals. IBM said it absorbs light at that wavelength 70 times more efficiently than silicon. Douglas Paul, who specialises in silicon germanium at the Cavendish Lab in Cambridge, said the frequency response achieved by the IBM team was impressive. IBM said the efficiency of its p-i-n detector was 40 per cent, although as EW went to press it was not clear if that referred to the internal or external quantum efficiency.

Professor Henning Sirringhaus is either very lucky, very good, or both. A man who got started in physics with the abstract idea of working on renewable energy, he has gone via a PhD in thin film silicon to leading a research group developing plastic electronics. The move would not be particularly remarkable if it happened today, but in 1998 plastic electronics was a newborn research area with an uncertain future. Uncertain enough for Sirringhaus's PhD supervisor at Princeton to question his sanity on taking a postdoctoral position with Sir Richard Friend in Cambridge University's Cavendish Lab. There was obviously risk involved in entering such a field, but Sirringhaus clearly is not satisfied with being bored. INSET: Industry seminar.

Patented techniques for creating patterns on silicon that alter the polarisation of incident light are being developed into usable devices at Innos, the recently launched silicon technology centre at the University of Southampton. The periodic metal-on-silicon and resist-on-silicon structures are two-dimensionally chiral, that is, their mirror image cannot be superimposed on them without taking it out of the plane of the surface. The technique could be used to make optical devices that are uniquely matched, and are immune to all other light signals.

A dedicated silicon technology centre providing advanced services to Great Britain and European industry has been created at Southampton University. The new venture, which is called Innos, has emerged from the EPSRC-funded Silicon Fabrication Facility, a centre which has offered research capability mainly to academics for the past 20 years. At the moment only five percent of Innos's work comes from industry, but it expects eventually to draw revenues worth£2.5m from these contracts. A direct-write electronic-beam machine capable of 10-15nm feature sizes is being added to a suite of installed kit worth about $30m.

Cambridge ultra wideband (UWB) developer Artimi has demonstrated the broadcast and reception of packet transmission via a wireless UWB network. The firm claims it is the first example of a UWB multimedia and data transmission in a real-world environment, from a standard NDIS driver on one PC to a standard NDIS driver on another. According to Mark Moore, Artimi's CTO, although the IEEE's 802.15.3a standard continues to go through a tortuous approval process, building a product was a crucial step for the firm, and ideally the first silicon will be software upgradeable to the emerging standards.

By using a novel structure called a metal-oxide semiconductor capacitor waveguide phase shifter, researchers at the software-based company Intel Corp. have succeeded in building an optical modulator capable of operating at up to 1GHz out of silicon. Such modulation speeds have until now been unobtainable from silicon, since the effects via which its diffractive index can be altered are relatively slow. Intel uses a transistor-like structure that enables the diffractive index to be varied by a technique called accumulation.

This year there will be a host of microdisplay-based rear-projection using liquid crystal-on-silicon and digital light projector. DAB radios sold like hot cakes over Christmas, but one still want multimedia content to connect receiver to a PC. Whether or not 5GHz wireless LAN makes any impact on the market this year, the vast bulk of 802.11a chips that do find action will be in complimentary metal oxide semiconductors. While switching speeds increase, effects on other aspects of transistor behaviour through shrinking the technology are not all positive

Researchers in Germany and Austria have found that high-k dielectric materials based on strontium can be grown directly on a silicon substrate and show promise for use as gate insulators in future process generations. As process geometries shrink, effects of quantum mechanical charge tunnelling through the conventional, low-k, silicon oxide gate insulator become increasingly important, since the tunnelling probability depends very strongly on the height of the energy barrier. In their work, published in the journal "Nature," scientists carried out first-principles calculations to determine the nature of the interface between silicon and the promising high-k dielectric.

The article discusses that using an inherently flexible material with some electronic properties to build transistors is a good idea, but that discounts crystalline silicon, and organic semiconductors. "We've put a lot of thought into this over the years and we can be quite clear," says Nigel Young, project leader for polysilicon displays with Philips Research. Young has worked on laying polysilicon circuits directly onto flexible plastic substrates. The advantages of steel include its ability to retain toughness even at very low thicknesses, and its thermal and electrical behaviour is also considerably more helpful than for plastics, which means it could be used in much larger displays. INSET: Performance and mobility.

Dye-sensitised solar cell has an efficiency of 10 per cent and could be produced at one-fifth the cost of existing silicon designs, claims a Swiss university. It uses an organic pigment supported on a porous TiO[sub2] substrate to harvest sunlight in a process similar to photosynthesis: electrons are liberated from pigment and cross the substrate to do work in an external circuit. In the past these organic systems have suffered from low efficiencies and susceptibility of dyes to breakdown under ambient conditions. For example, thermally induced stress at dye-substrate interface and dissolution of active materials in any residual water trapped in the cell.