The influence of an ultrathin Ni interface layer on the performance of GaN-based 380 nm UV LED with sputtered Zn1−xMgxO: Al transparent p-type electrode
| Autor: | Michał A. Borysiewicz, Marek Wzorek, M. Masłyk, M. Ekielski, K.D. Pągowska, Eliana Kamińska |
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| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Materials science Annealing (metallurgy) Band gap Metals and Alloys Analytical chemistry 02 engineering and technology Surfaces and Interfaces Crystal structure Sputter deposition 021001 nanoscience & nanotechnology 01 natural sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials law.invention law 0103 physical sciences Electrode Materials Chemistry Irradiation Crystallization 0210 nano-technology Diode |
| Zdroj: | Thin Solid Films. 649:61-68 |
| ISSN: | 0040-6090 |
| Popis: | In the present work we analyze the Zn1−xMgxO:Al/Ni/p-GaN system as a transparent electrode for GaN-based UV-LEDs. We first study the properties of the Zn1−xMgxO:Al films obtained by DC magnetron sputtering under various conditions and find that they exhibit anomalous crystallization behavior i.e. not all Mg substituted Zn in the ZnO crystal lattice creating Mg precipitates as well as a lack of correlation between the Mg content and film band gap. Subsequently, we study the behavior of the contact with ultrathin Ni films (2.5–10 nm) introduced at the interface with p-GaN both after deposition as well after annealing steps at temperatures from 400 °C to 750 °C. We use complementary techniques to discuss the structural and chemical properties of the material. We find that the Ni interlayer improved the properties of electrodes, especially their electrical parameters - a 2–3-fold increase in the current at a bias of 2 V was observed. Finally, in a full LED structure, we obtained an enhancement of the 380 nm irradiated power by 9.5% for the Zn1−xMgxO:Al/2.5 nm Ni electrode in comparison with a diode without the Ni interlayer. |
| Databáze: | OpenAIRE |
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