Improved performance of GaInN based deep green light emitting diodes through V-defect reduction

The strong correlation between V-defect density in the active region and light output power of GaInN based green and deep green light emitting diodes (LEDs) has been evaluated. The formation of such defects is confirmed as the major cause for rough growth morphology, drift of well and barrier widths, emission linewidth broadening, large color shift with current density, and thus poor light emission performance. We have optimized the epitaxial processes for the active region and successfully eliminated such defects from the entire device structure. The electroluminescence intensities from these V-defect-free devices with dominant wavelengths ranging from 520 to 570 nm, improve by a factor of two under high injection current density up to 100 A/cm2. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)