16:30 〜 16:45
▲ [12p-N101-13] 14 Milliwatt Operation of Highly Transparent AlGaN-Based (254-258 nm)-Band DUV LED
キーワード：AlGaN, DUV LED, (254-258nm)-band emission
Design of highly transparent AlGaN-based deep-ultraviolet (DUV) light-emitting-diode (LED) structures at (254-258nm)-band emissions were grown by metalorganic chemical vapor deposition (MOCVD) at 1160°C under 76 Torr pressure. Two types of DUV LEDs at 258 nm and 254 nm emission, respectively, were fabricated to investigate the external-quantum-efficiency (EQE) and light power (L) using pure p-AlGaN contact layer (by omitting p-GaN contact layer). The 258nm-band DUV device’s structure comprised an AlN template (4 µm) on a C-Sapphire substrate (400 µm), an n-type Al0.74Ga0.26N:Si electron source layer (ESL), AlGaN MQWs, an Al0.74Ga0.26N (blocking)/ Al0.55Ga0.45N (Valley):Mg multi-quantum-barrier electron-blocking-layer (p-MQB EBL), and a p-AGaN:Mg hole source layer (HSL) including p-AlGaN:Mg contact layer. The Al composition in the quantum-wells (QW) and quantum-well-barrier (QWB) of the MQWs were 60 and 74%, respectively. In second 254nm-band DUV LED device, MQWs parts of the previous design was replaced with Al composition in the wells and barrier layers of the MQWs were 64 and 78%, respectively. Ni/Au and In (dot) electrodes, respectively, were evaporated as a (n) p-contacts on the p-AlGaN:Mg contact and n-AlGaN:Si ESL in both devices. (254-258nm)-band AlGaN DUV LEDs containing a transparent p-AlGaN layers are reported in this paper.
The DUV LEDs showed relatively improved efficiencies on wafer of 2.2% at 258 nm emission and 1.2% at 254 nm emission both under CW and pulse-operation, respectively. The light power of 14 mW and 3.8 mW, respectively, at 258 nm and 254 nm emissions, respectively, on wafer under pulse-operation were achieved. The DUV LED showed a relatively good electrical contact with operating voltage of 22 V at 20 mA , which is comparable with the p-GaN DUV LED.
The DUV LEDs showed relatively improved efficiencies on wafer of 2.2% at 258 nm emission and 1.2% at 254 nm emission both under CW and pulse-operation, respectively. The light power of 14 mW and 3.8 mW, respectively, at 258 nm and 254 nm emissions, respectively, on wafer under pulse-operation were achieved. The DUV LED showed a relatively good electrical contact with operating voltage of 22 V at 20 mA , which is comparable with the p-GaN DUV LED.