Licht-im-Terrarium: Literaturdatenbank

LED materials for incandescent lighting are based on thin Gallium-Nitride layers. Due to the lack of Gallium-Nitride substrates such layers are usually grown as thin crystal layers on sapphire or silicon-carbide substrates. Gallium-Nitride grown on silicon is a material platform which offers a huge benefit as low substrate cost, large substrate diameter, and also opens a route for manufacturing in depreciated Si wafer fabs. But long GaN on Si was believed to be a niche and not suited for high performance devices. This is because material growth requires processes with temperatures above 1000 °C and thermal stress leads to cracking of layers even below device relevant thicknesses. In the last 15 years these problems have been solved and today GaN on Si based LEDs are competitive to GaN on sapphire based devices. This chapter describes the development of GaN on Si LEDs, the differences to GaN on sapphire based structures and different routes for achieving a high output power although these layers are originally grown on a light absorbing substrate.