Recent Progress in High Brightness LED Technology and Applications

The High Brightness Light Emitting Diode (HB LED) market is exploding as unit shipments continue their upward growth, according to new research. LEDs are creating a niche market for conventional suppliers of semiconductor processing tools. Markets for HB LEDs, backlight LEDs, and OLEDs are forecast.

Solid-state lighting (SSL), particularly light-emitting diode (LED) based SSL, is on course to become the dominant technology across all lighting applications. The luminous efficacy of SSL has surpassed previous lighting technologies and still has significant room to improve, and the price has decreased to the point where it is no longer a barrier to adoption for consumers. The LED technology platform also offers the opportunity to advance beyond legacy form factors, which embody the limitations of the previous lighting technologies; to move past the legacy functionality of providing basic illumination; and to enable energy savings beyond improved source efficiency to encompass more precise delivery of more suitable light at the appropriate time.

This explosion of applications is driven by two main directions: the ability to produce very small GaN LEDs (micro-LEDs and nano-LEDs) with high efficiency and across large areas, in combination with the possibility to merge optoelectronic-grade GaN micro-LEDs with silicon microelectronics in a hybrid approach. GaN LED technology is now even spreading into the realm of display technology, which has been occupied by organic LEDs and liquid crystal displays for decades. In this review, the technological transition toward GaN micro- and nanodevices beyond lighting is discussed including an up-to-date overview on the state of the art.

Organic light-emitting diodes (OLEDs) represent an area of SSL technology that can create diffuse light sources with direct emitters that are thin profile and bendable. This technology can produce new form factors and lighting design flexibility not available with today's LEDs or traditional lighting technology.