Introducing a thin InGaN interlayer with a relatively lower indium content between the quantum well （QW） and barrier results in a step-like InxGa1-xN/GaN potential barrier on one side of the QW. This change in the a...Introducing a thin InGaN interlayer with a relatively lower indium content between the quantum well （QW） and barrier results in a step-like InxGa1-xN/GaN potential barrier on one side of the QW. This change in the active region leads to a significant shift in photolumineseence （PL） and electroluminescence （EL） emissions to a longer wavelength compared with the conventional QW based light-emitting diodes. More importantly, an improvement against efficiency droop and an enhancement in light output power at the high-current injection are observed in the modified light-emitting diode structures. The role of the inserted layer in these improvements is investigated by simulation in detail, which shows that the creation of more sublevels in the valence band and the increase of hole concentration inside QWs are the main reasons for these improvements.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61334005,51272008 and 60990314the Beijing Municipal Science and Technology Project under Grant No H030430020000the National Basic Research Program of China under Grant Nos 2012CB619304 and 2012CB619306
文摘Introducing a thin InGaN interlayer with a relatively lower indium content between the quantum well （QW） and barrier results in a step-like InxGa1-xN/GaN potential barrier on one side of the QW. This change in the active region leads to a significant shift in photolumineseence （PL） and electroluminescence （EL） emissions to a longer wavelength compared with the conventional QW based light-emitting diodes. More importantly, an improvement against efficiency droop and an enhancement in light output power at the high-current injection are observed in the modified light-emitting diode structures. The role of the inserted layer in these improvements is investigated by simulation in detail, which shows that the creation of more sublevels in the valence band and the increase of hole concentration inside QWs are the main reasons for these improvements.
