Osram Researchers Win German Future Prize

2007-Dec-07 |  A team of researchers from the Siemens subsidiary Osram has won the 2007 German Future Prize. Federal President Horst Köhler presented the award on Thursday in Berlin. For a project entitled “Light from Crystals,” researchers have developed a new process for manufacturing highly efficient, long-life light sources from light-emitting diodes (LED). The €250,000 prize has now been awarded to Siemens for the third time since it was inaugurated 11 years ago.

The members of the prize-winning team include Dr. Stefan Illek and Dr. Klaus Streubel of Osram, who are pioneers in the field of “thin-film” technology, and Dr. Andreas Bräuer of the Fraunhofer Institute for Applied Optics and Precision Engineering in Jena. This technology makes it possible to produce extremely bright LED chips and to position them very closely to one another, thus creating a larger luminous field. These ultra-efficient LEDs from Osram can be used in mini-projectors, rear-projection TVs, and night-vision equipment in cars, to name a few applications. They also are suitable for general lighting purposes and headlights in vehicles.

The Ostar Lighting, for example, a small LED spotlight, has a luminosity of over 1,000 lumens, which makes it brighter than a 50-watt halogen lamp. It can therefore provide sufficient lighting for a desk from a height of two meters. What’s more, its small size also makes entirely new lamp designs possible.
LEDs consist of semiconductor crystals that emit light when an electrical current flows through them. During production, these crystals grow on a substrate. With conventional manufacturing techniques, this substrate remains in the diode, where it absorbs a large part of the light generated. Using the thin-film technology from Osram Opto Semiconductors, the upper surface of the light-generating layer is covered with metal in a process known as vapor-deposition. The resulting metallicized surface is then soldered to a thin carrier and acts as a reflector. Meanwhile, the original substrate is removed. This produces a thin light-generating layer very close to the surface of the LED. As a result, the diode emits almost all the light in a direction perpendicular to the reflector, which means a great increase in brightness.

Siemens researchers have been nominated for the German Future Prize a total of seven times. They were among the winners in 2004, with a mini-laboratory for medical diagnostics, and 2005, with a piezoelectric fuel-injection system for vehicles