title: Low temperature solution process-based defect-induced orange-red light emitting diode.
abstract: We report low-temperature solution-processed p-CuO nanorods (NRs)/n-ZnO NRs heterojunction light emitting diode (LED), exploiting the native point defects of ZnO NRs. ZnO NRs were synthesized at 90 °C by using hydrothermal method while CuO NRs were synthesized at 100 °C by using microwave reaction system. The electrical properties of newly synthesized CuO NRs revealed a promising p-type nature with a hole concentration of 9.64 × 10(18) cm(-3). The current-voltage characteristic of the heterojunction showed a significantly high rectification ratio of 10(5) at 4 V with a stable current flow. A broad orange-red emission was obtained from the forward biased LED with a major peak at 610 nm which was attributed to the electron transition from interstitial zinc to interstitial oxygen point defects in ZnO. A minor shoulder peak was also observed at 710 nm, corresponding to red emission which was ascribed to the transition from conduction band of ZnO to oxygen vacancies in ZnO lattice. This study demonstrates a significant progress toward oxide materials based, defect-induced light emitting device with low-cost, low-temperature methods.
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Pranab
authors.initials: P
authors.lastname: Biswas
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Sung-Doo
authors.initials: SD
authors.lastname: Baek
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Ji-Hyeon
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Su Jeong
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: College of BioNano Technology, Gachon University, 1342 Seongnamdae-ro, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-701, Republic of Korea.
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Myoung