Intended for CDMA and TDMA applications in the 1.8 to 2GHz band, Ericsson’s PTF10112 RF transistor employs Goldmos technology to improve overall RF performance.

With a minimum output power of 60W at 1dB compression, the device is a suitable alternative to identically packaged MRF286 types. It offers a gain of around 3dB higher than bipolar equivalents and operates from a standard 28V supply.

The device has a typical efficiency of 41% and can provide a thermal resistance of 0.74 degrees C/W and a drain-source breakdown voltage of 65V. The minimum power gain is 12dB at 1.95GHz, and each device exhibits a flat response of +/-0.3dB over the 1.93 to 1.99GHz PCN band.

Ericsson Microelectronics has launched three RF power transistors for use in GSM1800 basestations. They have a total gain of 33.5dB and offer good linearity and thermal stability which makes the suitable for D- Amps and the latest Edge basestations.

Working in the 1.8 to 2.0GHz frequency band, the 28V line-up comprises 5W PTF10107, the 12W PTF10053 and the 60W PTF10153. Total gain is a flat 33.5dB, exhibiting a high peak to average power capability which is particularly important in applications with high data rates, such as Edge.

All the devices use Goldmos technology and gain is typically 3dB higher for each device than its bipolar equivalent.

The PTF10107 pre-driver has a return loss of -27dB at 1.975GHz at 50 OHM impedance. As a result, reflections between the line-up’s input stage and the output of the previous stage are minimised. That in turn is said to increase the gain and efficiency of the overall circuit.

The use of Goldmos is also said to offer thermal stability. The drain current decreases with an increase in temperature.

With the PTF10107 and PTF10053 measuring 4 x 5mm and the PTF10153 measuring 20 x 34 including flanges, the line up is suitable for use where the board space is limited.

Available in block configuration or as stand-alone unit, GIPO high voltage pulse generators can produce pulses that can reach 5.5 kV with rise time of 2.5 ns. With adjustable pulse length from 200 ns to 30 [micro]s, they can be utilized in applications where it is necessary to switch high voltage quickly. Generators can be used with pockel cells, multi channels plates, intensified CCDs, laser diodes, and flash lamps.

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SDS (Systems Development & Solutions) based in France has introduced high voltage pulse generators based on the use of field-effect transistor technology. These compact GIPO generators can produce pulses that can reach 5.5kV with a rise time of around 2.5ns. The pulse length is adjustable from 200ns down to 30[micro]s. The GIPO is available either in a block configuration or as a stand-alone unit.

These high voltage pulse generators can be used in several applications where it is necessary to switch high voltage quickly. The GIPO series can be used with:

o Pockel Cells

o Multi Channels Plates

o Intensified CCDs

o Laser Diodes

o Flash Lamps

SDS manufactures a line of high voltage pulse generators and power supplies based on this technology.

In semiconductor manufacturing, fabricating smaller transistors and placing them closer together on a silicon integrated-circuit chip translates into faster computers.

Today’s advanced microprocessor chip has wires and surface features no thinner than 0.35 micrometer. To reach the high levels of performance that many researchers and others would like to see in future computers, manufacturers must develop technologies that significantly decrease that thickness.

The announcement last week of the formation of a private industry consortium called the Extreme Ultraviolet Limited Liability Company marked the launch of a major project aimed at developing the technology needed to etch circuit lines less than 0.10 [micro]m wide.

National Laboratory, the Sandia National Laboratories in Livermore, and the Lawrence Berkeley (Calif.) National Laboratory to work under the umbrella of the newly created Virtual National Laboratory (VNL). The industry group will provide $250 million to VNL over the next 3 years to develop extreme ultraviolet lithography for commercial manufacturing of computer chips.

A crucial part of semiconductor manufacturing involves an essentially photographic process of printing patterns to guide which parts of a silicon surface must be etched away. The industry co group is betting that the use of electromagnetic radiation at a wavelength of 13 nanometers, pioneered at Sandia, can be successfully put into an industrial setting.

A research team led by Jakub Kedzierski at the University of California at Berkeley has developed a transistor with a 15nm (0.015 micro m) gate using electron beam lithography.

One of the major problems with thin silicon-on-insulator systems is the large series resistance of the insulator layer. The team used two low barrier silicide source/drains in a 100nm layer that was thinned to 14nm to get round the problem.

As the silicide source/drain switches on, it passes through the source body flat band condition and so the body of the silicon blocks the current flow. Above this condition, the Schottky barrier is the dominant current barrier.

A dual high-voltage transistor (BF485PN) in the SC74 (SOT457) mini surface-mount package has been launched by Philips Semiconductors.

Targeted at the comms market, the next-generation device makes it possible to replace two large SOT54 leaded packages with a single, much smaller, surface mount device. This is also said to save on board space.

Used for the phone hookswitch, the device has the latest lead frame which has an improved power dissipation of 600mW.

British manufacturers will be hoping that the next 12 months can only get better, after a turbulent year dominated by the impact of the strong pound. The 13 per cent surge in the value of sterling against the German mark last year severely hit exporters to continental Europe and but all the signs are that the painful squeeze on profit margins will continue.

Even firms with no major overseas markets felt the pressure in 1997 as cheaper imports flooded in, while large engineers with far-flung global interests suffered when translating their profits into sterling.

The result was that share prices fell behind. The FTSE General Industrials index lagged the broader market by 18 per cent while the unloved Diversified Industrials sector, helped by two profit warnings from BTR, underperformed by over 30 per cent. Although the pound may weaken slightly during 1998, most forecasters predict it is unlikely to give up all the gains it made in 1997. Most economists are expecting further interest rate rises to curb inflation, with base rates unlikely to drop back until the second half of 1998. Higher rates will inevitably continue to support sterling. Those hardest hit by the strong pound will remain groups such as British Steel, which price products in German marks on world markets. British Steel has accelerated the contraction of its workforce to cut costs, but the longer the strong pound continues, the harder and more costly it becomes for companies to hedge against currency risks. Similarly, businesses which have long-term supply contracts in continental Europe, such as Laird, the car parts supplier, look vulnerable. Another question mark hangs over demand from the home market, with some forecasters predicting that the consumer boom will begin to fade as the stream of building society windfall payouts dries up. Though any impact on manufacturers would be gradual, the first signs could come in the car market, which is unlikely to grow much further than the 2.1 million sales due for 1997. Elsewhere, manufacturers will become increasingly preoccupied with consolidation. European defence contractors and their suppliers will contemplate moves to create a single, European giant to challenge the US. British Aerospace and GEC are ready to get together with their counterparts in Germany and Italy to form large defence groupings that can compete on a global scale. But a question mark remains about the attitude of the French government. If it continues to resist deals involving Thomson, the defence electronics group, British defence contractors may decide to look elsewhere - possibly even the US - for tie-ups. The steady streams of bids will continue, as globalisation becomes the by-word in the metal-bashing sector. As the recent offers for T&N, Morris Ashby and Menvier-Swain show, foreign predators have been keen to buy UK manufacturers as a way to build up their positions in Europe.

OL’ “TWO BRAINS” is back. So is “Doris Karloff”. From some of the press coverage one might be forgiven for thinking that the Leader of the Opposition had spent yesterday casting for a Hammer horror movie rather than restructuring his frontbench team. The impression is doubly unfortunate in that Mr Hague has promoted politicians like David Willetts and Ann Widdecombe who, despite their fearsome reputations and B-movie nicknames, are more likely to impress the voters than those they have replaced. Miss Widdecombe in particular has shown what wit, ability and a combative disposition can do even in an age when spin and looks are assumed to count for all. She, along with most of the rest of us, was obviously quite wrong to write her political career off after her celebrated “something of the night” attack on Michael Howard.

True, Miss Widdecombe, Mr Willetts and the new shadow Chancellor, Francis Maude, have “form”, but they are not readily recognisable as relics of the last government and thus “yesterday’s” men and women. Mr Hague has also tilted his team towards a fresher future by saying good-bye to Sir Brian Mawhinney, for so long the unacceptable face of Majorism. But to replace him as shadow Home Secretary with Sir Norman Fowler, a man who has been around so long that he was in Margaret Thatcher’s Shadow Cabinet twenty years ago, is to replace yesterday’s man with the day before yesterday’s man.

But then, does anyone care who the shadow Chancellor is? Does your heart beat a little faster now that you know that Peter Ainsworth is shadow Culture Secretary? After all, even if Labour had only squeaked in last time there would still be three or four years before the next election. And, if the pollsters and the wiseacres are to be believed, none of Mr Hague’s team has much chance of being in a position to run anything for the best part of ten years, if then. But these moves do matter, for these people are the alternative government. In the meantime their job is to oppose - and we should also care about the quality of political opposition, as fresh doubts are aired about the effectiveness of Parliament and the concentration of power at No 10. Harold Macmillan thought that opposition should be “fun”. He may have gone too far in suggesting that it should be entirely unencumbered by a sense of responsibility, but the need for a team of hard-hitting, lively parliamentarians, not above a bit of knockabout, has rarely been more keenly felt. Yesterday marked the end of what one of Mr Hague’s aides called his “interim” team. But, while there is yet some talent to promote, there are still a few too many of “yesterday’s men” on the opposition front bench for the current line-up to be definitive. This will not be the last reshuffle before we really see a fresh future for the Tory party. But let us hope Mr Hague has given himself some more leverage against a government that has rarely been effectively opposed.

McNamara was helping out at his local amateur club, Skirlaugh, on Saturday when he tripped while carrying a crate of bottles, cutting his palm and damaging nerves and tendons. Three hours of surgery at Hull Royal Infirmary saved his career, but the player is understandably disappointed at missing the tour to Papua New Guinea, Fiji and New Zealand. The players fly out on Friday.

“I had got my move from Hull to Bradford in the hope of more international honours, and I was playing well there,” McNamara said. “I have been lucky in one way because I nicked the artery and the doctors have told me that if the main cut had been there I could have lost my hand.” McNamara is replaced by Barrie-Jon Mather, the former Wigan centre or second-row and an England World Cup player. Mather has spent this season with Perth’s Western Reds after transferring from Wigan. Wigan have joined Sheffield Eagles and St Helens in making an inquiry for Warrington’s pounds 1.35m transfer-listed Iestyn Harris. Warrington are to sign the Wigan and former Great Britain hooker Martin Dermott, and the New Zealand second-row Tony Tatupu.

Charges move more slowly through plastic transistors than they do through transistors based on inorganic semiconductors such as silicon, the stuff of conventional electronics. The new findings indicate that this sluggish rate stems from a ball-and-chain effect: Traveling charges distort the organic materials’ malleable crystal lattices and then have to drag around those distortions.

Such understanding of the fundamental behavior of organic semiconductors is vital to the future of the technology, comments Allen Goldman of the University of Minnesota, Twin Cities.

Some flat-screen computer displays already exploit organic semiconductors as light-emitting pixels. However, the range of future uses is expected to mushroom to include such products as electronic newspapers (SN: 1/31/04,p. 67) and digital gadgetry sewn into clothing (SN: 11/20/99, p. 330).

Researchers have had a tough time getting a clear picture of how charges move in organic semiconductors. That’s because structural defects invariably riddle the thin crystalline films required for making transistors or other devices. Those defects dominate any moving charges’ behavior, thereby blinding researchers to the crystal’s intrinsic contribution to electronic movement.

The Rutgers-Illinois team reports the first organic transistor structure sufficiently free of crystal flaws for the intrinsic behavior of the organic material to stand out. In a yearlong progression of eliminating ever more defects, the researchers have boosted by as much as 200-fold the speed at which charges traverse their transistors.

“That’s definitely an amazing leap ahead,” says Alberto F. Morpurgo of the Delft University of Technology in the Netherlands.

Made of a thick and uniform crystal of the organic chemical rubrene, the structure also has an insulating gap of air instead of a layer of electrically insulating material, which would initiate defects in the crystal. The team, led by Michael E. Gershenson of Rutgers and John A. Rogers of Illinois, describes its work in an upcoming Physical Review Letters.

In their tests, the researchers observed changes in charge speed that theoretical studies and other experimental work have linked to lattice distortions, they say.

The new findings are “technically impressive,” comments Morpurgo. “Two years ago, [attaining] these results would have been considered science fiction,” he says.

Although organic semiconductors will probably never pose a speed challenge to silicon, traits such as their flexibility offer important advantages, Podzorov says. To match those advantages with maximum performance, he notes, researchers must figure out how to eliminate crystal defects in the thin-film components actually used in products.