title: Effect of Light Absorption in InGaN/GaN Vertical Light-Emitting Diodes.
abstract: For evaluating the effect of light absorption in vertically structured thin film light-emitting diodes (VLEDs), we investigate the dependence of the efficiencies on the several specific parameters including thickness and doping concentration (N(D)) of the n-GaN layer, a design of hetero-structures of the n-GaN layer, and a number of pairs of multi-quantum wells (MQWs). Generally, there is a complementary relation between internal quantum efficiency (IQE) and light extraction efficiency (LEE). However, we confirmed that LEE determined by light absorption is more dominant than IQE in VLED structures with a textured surface, from numerical simulation and experimental results. Effect of light absorption is more prominent in the vertical chip with a textured surface than in that with a flat surface, because a travel length of light extracted from the textured surface is longer. Minimizing light absorption in VLEDs is a key technology for improving light output, and light absorption speaks for the index of enhancement by the general technologies for improving LEE.
authors.forename: Junho
authors.initials: J
authors.lastname: Sung
authors.forename: Ki-Seong
authors.initials: KS
authors.lastname: Jeon
authors.forename: Min Woo
authors.initials: MW
authors.lastname: Lee
authors.forename: Eun Ah
authors.initials: EA
authors.lastname: Lee
authors.forename: Seon Ock
authors.initials: SO
authors.lastname: Kim
authors.forename: Hooyoung
authors.initials: H
authors.lastname: Song
authors.forename: Hwanjoon
authors.initials: H
authors.lastname: Choi
authors.forename: Mingu
authors.initials: M
authors.lastname: Kang
authors.forename: Yoon-Ho
authors.initials: YH
authors.lastname: Choi
authors.forename: Han-Youl
authors.initials: HY
authors.lastname: Ryu
authors.forename: Beom-Hoan
authors.initials: BH
authors.lastname: O
authors.forename: Jeong Soo
authors.initials: JS
authors.lastname: Lee