Nucleation and interface chemistry of ZnO deposited on 6H-SiC -: art. no. 155302

Self-assembled ZnO islands were nucleated on Zn-passivated 6H-SiC substrates under the compressive strain. The driving force Delta a/a and surface energy are the key parameters for the formation of islands and transition to coalescences/grains and a considerable modification of the band structure and structural properties of ZnO epilayers. Transmission electron microscopy (TEM) reflected defects near the ZnO/SiC heterointerfaces that have extended along the ZnO growth direction to be <= 130 nm, while the high-resolution TEM diffracted the polycrystalline interlayer in the ZnO/SiC heterointerface to be 2-3 nm. Formation of polycrystalline interlayer and columnar growth mode along the [0001] has been attributed to the accumulation of misfit dislocations, dangling atomic bonds, and imbalanced charge distribution in the II-VI/IV materials system, together with complex impurity matrix interdiffused/contributed from the host material, SiC substrate, and metalorganic precursors.