In this paper, we proposed quantum dot （QD） based structure for implementation of white light emitting diode （WLED） based on InGaN/GaN. The proposed structure included three layers of InGaN QD with box shapes and ...In this paper, we proposed quantum dot （QD） based structure for implementation of white light emitting diode （WLED） based on InGaN/GaN. The proposed structure included three layers of InGaN QD with box shapes and GaN barriers. By using of single band effective mass method and considering strain effect, piezoelectric and spontaneous polarizations internal fields, then solving Schr/Sdinger and Poisson equations self consistently, we obtained electron and hole eigen energies and wave functions. By evaluating dipole moment matrix elements for interband transitions, the output intensity was calcu- lated due to the interband transition between two energy levels with highest emission probability. We adjusted QDs dimensions and material compositions so that the output light can be close to the ideal white light in chromaticity diagrams. Finally, effects of temperature variations on output spectrum and chromaticity coordinates were studied. We demonstrated that temperature variations in the range of I00 to 400K decrease output intensity, broaden output spectral profile and cause a red shift in three main colors spectrums. This temperature variation deviates （x, y） are coordinated in the chromaticity diagram, but the output color still remains close to white.展开更多
文摘In this paper, we proposed quantum dot （QD） based structure for implementation of white light emitting diode （WLED） based on InGaN/GaN. The proposed structure included three layers of InGaN QD with box shapes and GaN barriers. By using of single band effective mass method and considering strain effect, piezoelectric and spontaneous polarizations internal fields, then solving Schr/Sdinger and Poisson equations self consistently, we obtained electron and hole eigen energies and wave functions. By evaluating dipole moment matrix elements for interband transitions, the output intensity was calcu- lated due to the interband transition between two energy levels with highest emission probability. We adjusted QDs dimensions and material compositions so that the output light can be close to the ideal white light in chromaticity diagrams. Finally, effects of temperature variations on output spectrum and chromaticity coordinates were studied. We demonstrated that temperature variations in the range of I00 to 400K decrease output intensity, broaden output spectral profile and cause a red shift in three main colors spectrums. This temperature variation deviates （x, y） are coordinated in the chromaticity diagram, but the output color still remains close to white.
