BEYOND THE HEDGES: UT professor finds better way to make light bulbs

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The compound, gallium nitride, was initially researched to produce a crystal that would emit blue light, similar to the green or red light that glows when an appliance like a computer is on. White light, the kind produced by light bulbs everywhere, is a composite of the red, green and blue areas of the light spectrum.

But the applications of the research by Russell Dupuis, a UT professor of electrical engineering in the Microelectronics Research Center at the Pickle Research campus, have surpassed his expectations.

Light-emitting diodes (LEDs), small green or red lights, are far more efficient than most conventional lighting, because they use less electricity and are far more durable and long-lasting, Dupuis said.

But, until now, the color blue was unavailable in LEDs; only red and green could be produced.

Until Dupuis' discovery, scientists had been unable to study the properties of gallium nitride, a compound which makes up blue LEDs.

The trick was "growing" the compounds into usable crystals using a process that has been developed in the last five years. Dupuis said he and his students have discovered a far better alternative to the five-year-long growth process.

Using this new method, engineers can grow usable samples of gallium nitride, which emit ultraviolet light when excited with a laser.

Combined with green and red LEDs, the new, blue LED will be able to imitate the white light spectrum and serve as a substitute for electrical light bulbs.

Soon, lights utilizing LED technology will be produced for everyday use, and the blue LED also promises to greatly improve CD technology, Dupuis said.

Compact disc players use lasers that produce light in the infrared spectrum to read the digital information off the disc and convert digital information to sound. Gallium nitride contains a substrate that can hold more data on compact discs by utilizing the ultraviolet spectrum rather than infrared light.

"It would be like getting Dr. Zhivago and Gone with the Wind on one CD," Dupuis said.

Source: The Daily Texan , Jan. 31.

This item appeared in the News section of the February 14, 1997 issue.

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