Compound Semiconductors

Osram holds the current lead in automotive LED sales but the emergence of LED headlamps could change the complexion of the market, says IMS Research. As automotive LED suppliers jockey for position in all-LED headlamps, GaN pioneer Nichia is looking to use its high brightness white LED expertise to dominate this market. The Japanese company's bid to make gains over Osram Opto Semiconductors and Philips Lumileds illustrates a key shift occurring in the automotive LED market recently documented by IMS Research. “At the moment most LEDs used in automotive, at least certainly in the exterior, are red and yellow, and Nichia doesn't produce many of those LEDs,” said IMS analyst Jamie Fox. “As we see more LEDs in front and interior lighting there will be more and more white nitride LEDs used, where Nichia is very strong.” The 2006 automotive LED market was worth $650 million, according to the IMS report “LEDs in Automotive Applications”. Osram OS was the largest supp...

The leading diode laser and consumer electronics manufacturer is hoping to push GaN lasers to longer wavelengths for color display applications. The field of non-polar GaN lasers, currently dominated by Rohm Corporation and the University of California, Santa Barbara, now has another big player in the shape of Sharp Corporation. This firm's researchers, like the other groups, have turned to this material to avoid built-in polarization fields found in conventional c -plane GaN. These fields reduce laser output efficiency and shorten emission wavelengths, in a blue-shift effect that worsens at higher injection currents. Sharp's 400nm blue laser Non-polar m -plane GaN doesn't have these fields, so substrates made of this material are promising candidates for fabricating blue lasers with longer wavelengths, nearer the green part of the spectrum (see related stories). Therefore, rather than the 400 nm laser diodes it makes using c -plane GaN for its Blu-ray pla...

If you asked somebody at random to name a semiconductor company, the chances are most people would say: "Intel". Now, there aren't really any compound semiconductor companies that make for household names (yet), but if you had to pick the "Intel" of the GaAs world, there's a fair chance that you'd say: "RF Micro Devices". These two firms are the kingpins in silicon and GaAs semiconductors. One thing that really characterizes them is their commitment to research and the development of new transistor technologies. It is, after all, Intel's Gordon Moore whose eponymous "law" is most closely associated with the forward march of semiconductor performance. Intel is not one for resting on its laurels. Months ahead of its rivals, it has just become the first to launch commercial designs based on the 45 nm technology "node". These designs are revolutionary transistors featuring metal gates and a high-k gate dielec...

A University of Florida professor is hoping to position GaN devices as robust and inexpensive electrical monitors for diabetes, renal failure and prostate cancer. Electronic detection of so-called biomarker molecules could accelerate disease diagnosis, and GaN transistors are one of the cheapest options available to achieve this. That's what Fan Ren of the University of Florida reckons, and he’s recently made his case by detecting a biomarker that signals acute renal failure down to 1 ng/ml. At this level, the researchers say that their device could be useful for preclinical and clinical applications. In a November 26 Applied Physics Letters paper, Ren and his collaborators modified a GaN high-electron mobility transistor (HEMT) from Nitronex by attaching kidney injury molecule-1 (KIM-1) antibodies to it. When KIM-1 is exposed to the transistor it then remains attached to the antibodies, affecting electron mobility and hence the current passing through the HEMT. KIM-1 is a molecule...

Weather radar is one of the few areas in which electron tubes still dominate solid-state electronics, but this is set to change thanks to a system from Toshiba. The world's first weather radar that uses a high-power semiconductor module, based on GaN, has been installed at Japan’s Nagoya University. Toshiba Corporation says that its GaN field effect transistors (FETs) allow it to manufacture systems without the electron tubes that have previously been used in weather radar transmitter modules. 21st century weather radar The initial 9 GHz radar has been made for Nagoya's Hydrospheric Atmospheric Research Center using Toshiba’s existing X-band GaN FET technology, and came into operation on November 28. The conglomerate will produce further individual X-band GaN radars to order and will also use its C-band FETs to make radars that operate in the 5 GHz range. A Toshiba spokesperson said that the development of semiconductor weather radar was made possible by its GaN products, becau...

High-efficiency triple-junction cells based on GaAs are again the key as Delft's Nuon Solar Team wins the Panasonic World Solar Challenge for the fourth year running. A team of students from Delft University in The Netherlands won last month's Panasonic World Solar Challenge using a car covered with GaAs-based solar cells. Nuon Solar's car, the Nuna4, completed the 3000 km race across Australia in 33 hours, beating its closest rival by 1 hour 36 minutes. The vehicle's top speed was 137 km/h and its average speed over the whole race was more than 90 km/h. Along with other solar cars, Nuna4 had to compete under extreme weather conditions as well as navigate between other traffic on the road from Darwin to Adelaide, including kangaroos and Australia's notorious road trains. "This race shows the public that not only can a car run on solar power, but also that it is fast," Tine Lavrysen, team spokesperson, told environmentalresearchweb . "Most people belie...