Industrial aspects of GaN/SiC blue light emitting diodes in Europe

The market of optoelectronic devices is continuously growing. Especially the development of hyper bright visible light emitting diodes (LEDs) leads into new applications such as automotive, signs and illumination. To serve these markets, low cost production processes have to be developed. The spectral region of blue and green is realized using GaN based devices. Such devices suffer from the availability of high quality substrates such as SiC or sapphire. Due to its conductivity, SiC is at Siemens AG the substrate of choice, even though it is quite expensive. On top of that, process control plays an important role for GaInN. Since there are lots of new, unsolved physical properties of this material, it becomes very important to overcome process related difficulties. One of the main problems is wavelength stability for different operation currents. As can be shown, there are possibilities to overcome these types of problems.