720130Improving the Efficiency of White High Brightness LEDs through Nano-TechnologyClosedGRD Development of PrototypeInnovate UKWhite High Brightness Light Emitting Diodes (HBLEDs) are made of alternating layers of nitride based materials called the active layer (AL) sandwiched between two layers of gallium nitride (GaN). Current designs of HBLEDs are limited in the amount of light they create due to inherent mechanical strain which creates lareg internal electric fields. The strain and hence field is unavoidable and causes two fundamental problems: a) it reduces the probability that an energetic electron can create light (quantum confined Stark effect) and b) at very high electrical currents, necessary to maximise the brightness of the LED, it encourages a non-light producing phenomenon (Droop) where the energetic electron transfers energy to a second, low energy electron. The internal field is eliminated by reducing mechanical strain. SPL has developed processing techinques to enable a standard large area HBLED to be etched into an array of hundreds of thousands of nano-rods, each with a diameter of a few hundred nanometres thereby reducing strain. In this way, SPL has created prototype diodes demonstrating that the brightness is significantly increased and that the Droop reduced. SPL has so far filed three patents based on its technology. The next development steps for SPL are; a) to optimising some of the key steps in the etching processes to maximise the effects and b) to prove that the processing techniques lend themselves readily to a mass manufacturing environment. We propose achieving this through the pilot scale manufacture of several batches of diodes. The project involves; a) capital expenditure (£130k) b) employment of 2 engineers. The extra resources together with existing facilities mean that we will be able to complete this project in 18 months. The project will also involve some sub-contract work to organisations that are expert in the conventional steps necessary to convert our processed chips into diode