Fig. 1. Schematic diagram for origins of room temperature ferromagnetism in dilute magnetic semiconductor.
Fig. 2. Room temperature magnetization curves for (ZnO 20Å/Co xÅ) multilayer (a) as-deposited (b) vacuum-annealed at 400℃ for 1 hour, and for (ZnO 40Å/Co xÅ) multilayer (c) as-deposited (d) vacuum-annealed at 400℃ for 1 hour.
Fig. 3. UV-Vis transmission of (ZnO 20Å/Co xÅ) multilayer (a) as-deposited (b) vacuum-annealed at 400℃
Fig. 4. XPS depth profiles of (ZnO 20Å/Co 3Å) multilayer (a) as-deposited (b) vacuum-annealed at 400℃
Fig. 5. HRTEM EDS analysis of (ZnO 20Å/Co 3Å) multilayer (a) as-deposited (b) vacuum-annealed at 400℃for 1 hour, and (ZnO 40Å/ Co 3Å) multilayer (c) as-deposited (d) vacuum-annealed at 400℃for 1 hour.
Table 1. (ZnO/Co)/ZnO multilayer specification.
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