Influence of Mg doping profile on the electroluminescence properties of GaInN multiple-quantum-well light-emitting diodes

The influence of the Mg doping profile on the electroluminescence efficiency of GaInN light emitting diodes (LED) has been investigated. The Mg doping profile is influenced by segregation as well as by diffusion during the growth. The diffusion of the Mg dopants into the active region can be controlled by the growth temperature of the Mg doped layers. An increase in Mg concentration close to the active region results in an improved hole injection and thus in a higher electroluminescence efficiency of the GaInN quantum wells. However an excessive spread of the Mg doping atoms towards the GaInN quantum well active region leads to nonradiative recombination and thus a lower output power of the LEDs. An LED test structure containing multiple quantum wells which differ in In content and emission wavelength was used to probe the spatial distribution of the radiative recombination of electrons and holes in the active region and to clarify the influence of Mg dopants in the active region on nonradiative recombination.

[1]  T. Taguchi,et al.  Compound semiconductor lighting based on InGaN ultraviolet LED and ZnS phosphor system , 2000, 2000 IEEE International Symposium on Compound Semiconductors. Proceedings of the IEEE Twenty-Seventh International Symposium on Compound Semiconductors (Cat. No.00TH8498).

[2]  Michael Heuken,et al.  Composition Fluctuations in InGaN Analyzed by Transmission Electron Microscopy , 2000 .

[3]  Joachim Wagner,et al.  (AlGaIn)N ultraviolet LED chips and their use in triphosphor luminescence conversion white LEDs , 2002, SPIE OPTO.

[4]  Joachim Wagner,et al.  Ultraviolet Pumped Tricolor Phosphor Blend White Emitting LEDs , 2001 .

[5]  P. Schlotter,et al.  Luminescence conversion of blue light emitting diodes , 1997 .

[6]  Akito Kuramata,et al.  Interwell inhomogeneity of carrier injection in InGaN/GaN/AlGaN multiquantum well lasers , 1998 .

[7]  Michael Kunzer,et al.  Origin of defect-related photoluminescence bands in doped and nominally undoped GaN , 1999 .

[8]  Michael R. Krames,et al.  High Power LEDs – Technology Status and Market Applications , 2002 .

[9]  B. Hahn,et al.  GaN-Based LEDs and Lasers on SiC , 2000 .

[10]  Michael Kunzer,et al.  Nature of the 2.8 eV photoluminescence band in Mg doped GaN , 1998 .

[11]  Shuji Nakamura,et al.  The Blue Laser Diode: GaN based Light Emitters and Lasers , 1997 .

[12]  Takashi Mukai,et al.  Phosphor Free High-Luminous-Efficiency White Light-Emitting Diodes Composed of InGaN Multi-Quantum Well , 2002 .

[13]  Shunro Fuke,et al.  Optical properties of hexagonal GaN , 1997 .