Author/Authors :
Seo، نويسنده , , Yong Gon and Baik، نويسنده , , Kwang Hyeon and Song، نويسنده , , Keun-Man and Lee، نويسنده , , Seokwoo and Yoon، نويسنده , , Hyungdo and Park، نويسنده , , Jae-Hyoun and Oh، نويسنده , , Kyunghwan and Hwang، نويسنده , , Sung-Min، نويسنده ,
Abstract :
Non-polar a-plane ( 11 2 ¯ 0 ) light-emitting diodes (LEDs) in InGaN/GaN multiple quantum well structures were successfully fabricated by metal organic chemical vapor deposition (MOCVD) directly grown on r-plane ( 1 1 ¯ 20 ) sapphire substrates. The full width at half maximums (FWHMs) of the X-ray rocking curve (XRC) of an a-plane GaN template along the c- and m-axes were measured to be ∼349 and ∼533 arcsec, respectively. The optical output power and external quantum efficiency (EQE) at drive currents of 20 mA and 100 mA under direct current operation in on-wafer measurements were 1.24 mW, 2.4% and 100 mA, 1.7%, respectively. The a-plane LED showed 2.8 nm blue shift with change in drive current from 5 mA to 100 mA. The polarization ratio at room temperature was 0.4 and it indicates that the a-plane LED has polarization anisotropy.
Keywords :
a-Plane , Non-polar , InGaN , Light-emitting diode , r-Plane sapphire , X-ray diffraction
