Soraa has received an award from the U.S. Department of Energy for its outstanding work in the development of high-efficiency m-plane LEDs grown on low-defect density bulk GaN substrates.
The company demonstrated a very high peak internal quantum efficiency (IQE of 88%), low efficiency droop (10% from 10Acm-2 to 100A.cm-2) and perfect wavelength stability (up to 200A.com-2) at a wavelength of 450nm LEDs.
Soraa’s GaN on GaN LEDs handle more current and emit substantially more light (about ten times) per area of LED wafer material than the conventional approach of depositing GaN layers on cheaper foreign substrates like sapphire, silicon carbide or silicon. The company’s GaN-on-GaN technology leverages the advantages of the native substrate, including lower crystal defect densities (by more than a thousand times), which allow reliable operation at very high current densities, the same principle that enabled Blu-ray laser diodes. In addition to improved crystal quality, the native substrate advantages of optical transparency and high electrical and thermal conductivity provide for a very robust, simple LED design for maximum performance. Another advantage of the GaN-on-GaN approach is the flexible choice of crystal growth plane, which has demonstrated advantages in high peak internal quantum efficiency and low-droop LED performance.