| Autor: |
Kykyneshi, R., Nielsen, B.C., Tate, J., Li, J., Sleight, A.W. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 12/1/2004, Vol. 96 Issue 11, p6188-6194, 7p, 1 Diagram, 2 Charts, 10 Graphs |
| Abstrakt: |
Transport and structural properties of Mg-doped and O-intercalated sintered powders and polycrystalline films of CuSc1-xMgxO2+y are reported. Substitution of Mg for Sc systematically increases the p-type conductivity in CuSc1-xMgxO2 sintered powders, producing a maximum conductivity of 0.015 S/cm at x≈0.06. A similar level of conductivity is observed in transparent polycrystalline CuSc1-xMgxO2 films at the same doping level. Mg doping causes no significant increase in optical absorption at this level. Intercalation of oxygen into the delafossite structure leads to a much larger increase in p-type conductivity. In powders, the maximum conductivity is 0.5 S/cm at y=0.23 and x=0.05. In oxygen-intercalated films, the maximum conductivity was 25 S/cm, with the transparent films gradually darkening as oxygen is incorporated. Oxygen intercalation increases the a-axis lattice parameter of the delafossite structure in both films and powders, with a much smaller effect on the c-axis parameter. Two distinct phases with y≈0 and y≈0.5 are observed in x-ray diffraction of powders. In films intermediate values of y are observed, often in combination with a distinct y=0 phase. The absorption properties of the powder samples indicate introduction of defects into the 2H polymorph of CuScO2 and CuSc1-xMgxO2 compared to the 3R polymorph. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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