Abstract
Blue InGaN/GaN multiple-quantum-well light-emitting diodes were grown on sapphire substrates by using a metal-organic vapor phase epitaxy system. A Mg-doped AlGaN electron-blocking barrier was introduced under various Cp2Mg flow conditions at a high temperature of 1050 °C. The characterization included current-voltage, capacitance-voltage and electroluminescence analyses. The luminescence efficiency showed an improvement of more than 90 % when the Cp 2Mg flow rate was increased from 50 to 200 sccm. The forward voltage was reduced to 3.18 V at 20 mA. The series resistance was also estimated to be 10.81 Ω. Secondary-ion mass spectrometry revealed the Mg doping profiles close to the quantum-well active region. The increased Mg concentration resulted in improved hole injection and carrier concentration. This is in agreement with the increased electroluminescence efficiency and luminous intensity and with the lower turn-on voltage. The X-ray diffraction study showed a full width at half maximum of 290.1 arcsec from the GaN (0002) diffraction and 325.9 arcsec from the GaN (101̄2) diffraction.
Original language | English |
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Pages (from-to) | 1570-1574 |
Number of pages | 5 |
Journal | Journal of the Korean Physical Society |
Volume | 52 |
Issue number | 5 |
DOIs | |
State | Published - 05 2008 |
Keywords
- Light-emitting diode
- Nitride
- Secondary-ion mass spectrometry