Abstract
Epitaxially grown ZnO thin films on 4H-SiC (0 0 0 1) substrates were prepared by using a pulsed laser deposition (PLD) technique at various substrate temperatures from room temperature to 600 °C. The crystallinity, in-plane relationship, surface morphology and optical properties of the ZnO films were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and photoluminescence (PL) measurements, respectively. XRD analysis showed that highly c-axis oriented ZnO films were grown epitaxially on 4H-SiC (0 0 0 1) with no lattice rotation at all substrate temperatures, unlike on other hexagonal-structured substrates, due to the very small lattice mismatch between ZnO and 4H-SiC of ∼5.49%. Further characterization showed that the substrate temperature has a great influence on the properties of the ZnO films on 4H-SiC substrates. The crystalline quality of the films was improved, and surfaces became denser and smoother as the substrate temperature increased. The temperature-dependent PL measurements revealed the strong near-band-edge (NBE) ultraviolet (UV) emission and the weak deep-level (DL) blue-green band emission at a substrate temperature of 400 °C.
Original language | English |
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Pages (from-to) | 179-182 |
Number of pages | 4 |
Journal | Journal of Alloys and Compounds |
Volume | 489 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2010 Jan 7 |
Keywords
- Crystal growth
- Luminescence
- Thin films
- X-ray diffraction
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry