Technology bulletin  3-23-98

March 23, 1998 Design News

Technology bulletin

Late developments that shape engineering

by Laurie Peach, Associate Editor

Are you seeing these colors yet?

The rose, a brilliant red. The sky, a purplish blue. The sunset, a soft magenta. If you are seeing these vivid colors, then you may be looking at the next generation of video screens or computer displays. If you aren't, that means the products aren't commercialized yet. But they are possible, thanks to a new blue laser, developed by Dr. E. Fred Schubert, professor of electrical and computer engineering and a member of the faculty of the Photonics Center at Boston University (Boston, MA). In the February 1998, Issue 4, of Electronic Letters, Schubert describes how he and Dean Stocker, a doctoral candidate in physics, fabricated the world's first gallium nitride (InGaN) double-heterostructure laser from tiny pieces of polished sapphire under even smaller layers of semiconducting crystal. The laser materials were scored with a diamond and then "cleaved"--or broken--along the scratch to produce smooth facets that control the paths of the photons that make up the laser beam. The blue laser may also expand the storage capacity of today's digital video disks up to four times. For more information, contact Joan Schwartz at (617) 353-4626, e-mail: [email protected].

Getting a grip on battery assembly

Engineers at TBS Engineering presented re-searchers at C4 Carbides (Cambridge, England) with a problem: Design an efficient gripping system for a new type of premium grade battery where lead cells are encased in a glass fiber compound. The lead plates weigh up to 15 kg and cannot be out of alignment during the production process or the battery will malfunction or fail. The C4 Carbides solution: A process where tungsten grit is metalurgically bonded with a nickel braze to almost any steel alloy substrate, achieving a coefficient of friction greater than 1.6. "Tungsten grit not only gives us the grip we require, without deforming the lead cells, but is also easy to keep clean as the lead oxide--a dirty and sticky substance--doesn't adhere to the surface," says Chris Barge, engineering manager at TBS. Tungsten grit is a rising star among precision gripping, grabbing, and clamping operations. Other applications include a cable clamp for submarine fiber optics and gripping clamps for the oil industry to protect the stainless steel pipes used in the extrusion of copper pipes. Phone Bob Nicolson at +44 (0) 1223-506406 or e-mail: [email protected].

One chip does work of two

Ever ask the Great Pumpkin for a reconfigurable printed circuit board (PCB) on a chip? Well, unlike Linus in the pumpkin path, Motorola Semiconductor Products Sector (Phoenix, AZ) developed a reconfigurable embedded system process. Its new CORE+ technology, according to company officials, is the world's first--combining standard, diffused components, and field programmable gate arrays (FPGA) on a single silicon substrate. "We've identified a niche opportunity for this advanced product," says Ron Lipinski, director of operations. Motorola took their in-house know how of microprocessors, microcontrollers, and digital signal processors and merged this with their FPGA ingenuity. "We can put whatever a customer wants on silicon," Lipinski adds. Existing processes require at least two chips. This not only means more money, but you lose performance because electrons take longer to move between them. The first product, expected out by the third quarter of 1998, will be "the industry's first hard diffused core." The MPACF250, designed with Motorola's 68K-compatible Cold-Fire architecture, combines 32-bit RISC with a memory-saving, variable-length instruction set. The CORE+ family will be supported by schematic capture, simulation, logic synthesis, compiler, code debugging and in-circuit emulation tools from several vendors. Contact Connie Schultejans at (602) 732-2852.

Go ahead, the water's fine

While drinking and driving may be hazardous to one's health, drinking the water in France is not. Saur, a water distribution company in France, installed electronic sensors and high-performance monitoring equipment on an aqueduct that supplies the drinking water for Disneyland Paris. The devices measure physico-chemical and biological data upstream of the water offtake and in the water-treatment plant. Escherichia Coli (E. Coli) levels, measured every two hrs, are used as harbingers of pathogens. Because the bacteria acidifies on glucose media, the Disneyland equipment holds 100 ml (3.4 oz) of water in a nutrient-rich cell and automatically measures the variation in pH. From this, it deduces the quantity of bacteria down to one bacterium in 100 ml. Traditional analysis time is 48 to 72 hrs. The new monitoring equipment provides results within 11 hrs. Marketed by Ysebaert, the system costs $34,000 to $38,000. Phone (312) 222-1237.

Filmless X-ray system on tap

X-rays without film. Fewer X-rays taken. Less radiation exposure. Real-time digital images that can be stored electronically or sent anywhere in the world via telecommunications systems. Such will be the change in X-ray technology with the large-scale, amorphous-silicon X-ray detectors developed by GE Medical Systems (Milwaukee, WI). Conventional X-ray film and chemicals are replaced with computer images and a large-format X-ray detector. Measuring up to 41 x 41 cm in the active area, GE says these are the largest panels available anywhere. The immense format and high pixel density eliminate the need for optical image reduction. Each pixel delivers up to 16 bits of dynamic-range (contrast) information. Officials at GE predict this will revolutionize the way X-ray images are acquired, analyzed and shared. The manufacture of the detector starts with a pizza-box-size, glass-panel substrate. Photolithographic techniques create photodiodes by applying and patterning successive thin-film layers of silicon, metals, and insulators. A final layer of scintillator material, which converts X-ray photons to visible light, is applied over the array. EG&G (Santa Clara, CA) will have exclusive rights to manufacture the panels, available for medical applications by late 1998 or early 1999. Phone (408) 565-0850.

Camera sniffs out deadly gases

Physicist Dr. Bijan Miremadi has developed a gas sensor that could prevent disasters caused by dangerous gases both at home and in the workplace. "To the best of our knowledge, this is the only one of its kind in existence," says Miremadi. Depending on the type of sensor heads they use, most gas sensors currently in the market are not selective to a particular gas. His system is like a sniffing camera which can find any gas and identify it. Miremadi developed two versions--a handheld unit suitable for personal use or in the home, and another unit that can be controlled by a computer and monitor multi locations in office buildings, industrial sites, and mines. The handheld version, now in the prototype stage, can also be connected to a computer or operated independently. Miremadi is currently looking for financing to bring his products to market. The sensor was developed with the support of SFU's university/industry liaison office, in collaboration with Western Pacific Research Corp., an SFU spin-off company.

Here comes porous silicon!

Although still three to five years away, computers based on light signals instead of electrical signals might put the Pentium chip to shame. Since 1992, scientists knew that the holes in porous silicon contain microscopic structures that emit light when electric current is applied. But the untreated material was fragile. Oxygen and water molecules in the air interact with the surface and create a glass-like coating that disrupts its photoluminescence properties. Jillian Buriak, assistant professor in Purdue's Department of Chemistry, discovered a way to stabilize the substrate's surface by coating the porous surface of the silicon with Lewis acid, a solution which produces a greasy coating. "Because most current technology is based on silicon, it may be relatively easy to develop the optical applications and combine them with current technologies, as the manufacturing processes are already in place," Buriak says. Porous silicon could easily serve as a flat, millimeter-thick display area for computer screens, as well as a basis for computers that operate on light signals.

Gas up your fuel cell

Regular unleaded gasoline may soon power fuel-cell vehicles. Arthur D. Little (ADL, Cambridge, MA), a technology-based consulting firm, completed a five-year program sponsored by the U.S. Department of Energy. Out of the study, rose a reformer technology that converts gasoline and other carbon sources to hydrogen on-board an automobile. Fuel cells then convert the hydrogen to electricity which powers the vehicle. Chrysler Corporation is working on a model of a fuel cell car and hopes to demonstrate a working vehicle with this technology in the next two years. "Using the current fueling infrastructure will shrink the time frame needed to achieve fuel cell-powered family sedans," states Jeffrey Bentley, a director in Technology and Product Development business. "Fuel cells require hydrogen to operate and hydrogen is something not sold at your neighborhood service station. This breakthrough technology represents the first time that gasoline can successfully operate fuel cells." The reformer incorporates a fuel flexible design, enabling a vehicle running on this technology to use a variety of fuels.

One BIG crystal

Step right up and see the world's largest crystal! It measures 52 cm (over 20 inches) across at the base and weighs nearly 500 lbs. With a lot of loving care, scientists at Livermore National Laboratory grew this single crystal optical element using a rapid- growth method. The fast growth method was pioneered in Russia and perfected at Livermore over the past fe