True-Red microLEDs will facilitate multicolor display success
Lumileds has extended its record-setting advances in its InGaN Red LED development. The InGaN material system is an attractive alternative to AlInGaP for creating red light sources because it harmonizes manufacturing with Green and Blue LEDs, which are also based on InGaN. The large industrial capacity of InGaN gives economies of scale and is preferred for integration with silicon semiconductor manufacturing. InGaN Red is especially promising for microLED applications because of its characteristic to maintain efficiency at micron-scale sizes and low current density.
Lumileds scientists are the first to demonstrate that rich deep red light (615nm dominant wavelength corresponding with 635nm peak) can be produced with InGaN LEDs, achieving a Wall plug Efficiency of 7.5% at a current density of 10A/cm². Lumileds’ breakthroughs address the challenges associated with high indium concentrations including spectral peak shifts and broadening with current density.
“The current efficiency for sub-10-micron red microLEDs is an impediment to cost-effective and efficient microLED displays,” said Rob Armitage, Director of Nitride Epitaxy Development. “Our work on Red InGaN validates our roadmap to meeting cost and efficiency thresholds for adoption.”
In addition to demonstrating high-efficiency Red InGaN, Lumileds successfully established Red, Green, and Blue light emission from a single InGaN epitaxial stack. Subsequently, Lumileds translated this into microLEDs with excellent color quality and electrical characteristics. The integration of the three primary colors into single microLEDs has a tremendous impact on achieving low-cost high-yield microLED display assembly and will ultimately enable compact full-color displays for Augmented Reality applications.
Rob Armitage, Director of Nitride Epitaxy Development at Lumileds is an invited speaker at the upcoming IWN 2024 conference where he will discuss the Development of InGaN LEDs for Color Display Applications.