| Autor: |
Z. John Zhang, Matthew H. Kane, Shalini Gupta, Nikolaus Dietz, Qing Song, Christopher J. Summers, Martin Strassburg, Ian T. Ferguson, Adam M. Payne, William E. Fenwick, Ali Asghar |
| Rok vydání: |
2006 |
| Předmět: |
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| Zdroj: |
Journal of Crystal Growth. 287:591-595 |
| ISSN: |
0022-0248 |
| Popis: |
Metalorganic chemical vapor deposition (MOCVD) has been used to grow high-quality epitaxial films of Ga 1-x Mn x N of varying thickness and manganese doping levels. No macroscopic second phases were observed via high resolution X-ray diffraction. Atomic force microscopy revealed MOCVD-like step flow growth patterns with a mean surface roughness as low as 3.78 A in lightly doped samples, and matched that of the underlying GaN template layers. No change in the growth mechanism and morphology with Mn incorporation is observed. A uniform Mn concentration in the epitaxial layers is confirmed by secondary ion mass spectrometry. SQUID measurements showed an apparent RT ferromagnetic hysteresis with saturation magnetizations as high as 2.4μ B /Mn at x = 0.008, which decreases with increasing Mn incorporation or reduced structural quality. Co-doping with either Si or Mg during the resulting growth process resulted in a large decrease in the saturation magnetization values. Competition for incorporation between Mn and Mg during the MOCVD growth process is observed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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