portfolioAbstract

NEWLED will develop high efficiency and high brightness monolithic and hybrid all-semiconductor WHITE light-emitting GaN-based diodes.

Power losses due to phosphor conversion and the problem of different ageing rates of the GaN LED pump will be eliminated by the development of phosphor free structures with increased brightness (power emitted per surface per angle). NEWLED will enhance the efficiency of yellow InGaAlP/AlGaAs LEDs by bandgap engineered superlattices. Novel light extraction approaches will target advanced directionality and colour adjustment. Values of 50 to 60% overall efficiency with a conversion of greater than 200 lm/W in the exploited warm white LEDs are targeted as well as the realisation of a colour rendering index (CRI) of greater than 95. Advanced packaging will enable effective heat dissipation and light management. The devices will have immediate applications in automotive, industrial lighting and displays industries. Widespread implementation would reduce global energy consumption by approximately 10% and reduce CO2 emissions by 3Bn tonnes with consequent economic and environmental benefits.

imgProject Details

  • Project Number: 318388
  • Project start date: 01/11/2012
  • Project end date: 31/10/2016

imgFunded by:

  • European Union
  • Seventh Framework Programme

Concept

NEWLED's objectives are to develop high brightness white LEDs with high CRI (>95) and efficacies of more than 200 lm/W. Dramatic reduction of internal and external losses in III-V semiconductors based LEDs is targeted by clear improvement of crystalline quality and significant enhancement of light extraction along the entire process chain from semiconductor epitaxial layer growth to the application (e.g. light engines) will pave the way to superior white LEDs capable of replacing all conventional light sources over the coming years. To achieve this, new knowledge on the control of semiconductor properties (point defects, interfaces, impurities, doping) on a near-atomistic scale is essential, requiring novel crystal growth, design and technology according to the different materials as planned for NEWLED. Novel crystal growth approaches will develop superior material that will be processed by best-in-class chip processes facilitating optimal current spreading and light extraction. The LED chips will be used for monolithic and hybrid LEDs and will be integrated in applications to be developed in close collaboration with the upstream process steps to take full advantage of the improvements achieved. Excellent light mixing for homogeneous illumination and a superior heat management will be included to realise lifetimes of more than 50k hours. The NEWLED consortium has been assembled to bring together highly recognised experts from academia and industry ensuring best material and process development supported by expert simulation and perfectly adapted rigorous analytical capabilities. Today the best R&D cold white LEDs wall plug efficiency exceeds 65%.

However, to overcome the variety of loss channels in the production of LEDs NEWLED will addresses every step of the LED fabrication process, ensuring each is well adjusted to avoid compromising the achievements of the overall process and to ensure significant system and operating cost reduction.

Objectives

The overall NEWLED objectives are to develop:

  • White LEDs with efficacy of 200 lm/W at a CRI >90 yielding wall plug efficiencies of applications > 60%
  • High brightness, high efficiency green LEDs emitting in deep green range
  • Phosphor-free materials for high efficacy, high brightness LED light engines
  • Efficiency enhancement of yellow InGaAlP/AlGaAs LEDs
  • Stability of colour coordinates over a lifetime > 50.000 hours