title: Improved electroluminescence from ZnO light-emitting diodes by p-type MgZnO electron blocking layer.
abstract: We report on the effect of a p-type MgZnO electron blocking layer (EBL) on the electroluminescence from n-type ZnO/undoped ZnO/p-type ZnO light-emitting diodes (LEDs). The p-type Mg(0.1)Zn(0.9)O EBL was introduced between the undoped and p-type ZnO layers. The p-type Mg(0.1)Zn(0.9)O EBL increased the ultraviolet emission by 140% at 60 mA and decreased the broad deep-level emission from ZnO LEDs. The calculated band structures and carrier distribution in ZnO LEDs show that p-type Mg(0.1)Zn(0.9)O EBL effectively suppresses the electron overflow from undoped ZnO to p-type ZnO and increases the hole concentration in the undoped ZnO layer.
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea.
authors.forename: Yong-Seok
authors.initials: YS
authors.lastname: Choi
authors.forename: Jang-Won
authors.initials: JW
authors.lastname: Kang
authors.forename: Byeong-Hyeok
authors.initials: BH
authors.lastname: Kim
authors.forename: Dong-Keun
authors.initials: DK
authors.lastname: Na
authors.forename: Sang-Jun
authors.initials: SJ
authors.lastname: Lee
authors.forename: Seong-Ju
authors.initials: SJ
authors.lastname: Park
mesh_terms: D004583:Electrons; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008029:Lighting / Q000295:instrumentation*; D008163:Luminescent Measurements / Q000295:instrumentation*; D008277:Magnesium Oxide / Q000737:chemistry*; D012666:Semiconductors; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D008277:Magnesium Oxide; D015034:Zinc Oxide