Dr. Martin Strassburg
(OSRAM Opto Semiconductors GmbH,  93055 Regensburg)

 The Future of Light

Optoelectronic devices based on group III nitrides (i.e., LEDs) provided a completely new technology in the lighting sector, the solid state lighting. There has been an incredible development in the recent more than 20 years: LEDs for illumination and projectors in mobile devices were just a vision for a far away future. Meanwhile, such devices are commodity based on the significant increase in their efficiency. This has been the driving force for about one decade. However this development has not fully accomplished yet. The recent improvements of the device design and in doping strategies yielded efficiencies close to the fundamental limit reaching internal quantum efficiencies of more than 90 %.

Nowadays, it is recognized that LED offer a big variety of opportunities beyond efficient lighting. There are many applications that could only be addressed by the unique characteristics of semiconductor LED light sources. Thus, it is much more than cost cutting triggering further research on group III nitride optoelectronics, such as e.g. hetero-integration of electronics and optoelectronics. Examples of technology and products for various application fields will illustrate the claimed technology leadership that is based on the close interplay of material development, thorough understanding of scientific background and of technological solutions yielding.

In addition to visible LEDs, deep ultraviolet light emitting diodes based on AlGaN and emitting below 300 nm are gaining more and more interest in industry and academia. This new LED technology has numerous applications and benefits over the existing conventional Hg discharging lamp technology and are ready to fulfil the necessary requirements to replace these traditional light sources, which have limited lifetimes and are contain toxic materials. DUV LEDs can be used for disinfection purposes, like water sterilization, for environmental and medical applications, but are also interesting for to be used as gas sensors.