Texture Structure Analysis and Crystalline Quality Improvement of CeO2(110) Layers Grown on Si(100) Substrates

The texture structure of epitaxially grown CeO2(110) layers on Si(100) substrates was investigated using high-resolution electron microscopy. Surface morphology observations using high-resolution secondary electron microscopy indicated that the layer reveals a surface morphology with stripes aligned in two perpendicular directions. High-resolution transmission electron microscopy analysis verified that the crystallographic in-plane directions of the two kinds of domains correlated with the two directional stripes are exactly perpendicular to each other. The texture structure is well explained crystallographically by the model, which has been proposed by the authors. It is found that silicon substrates with off-orientation of ∼0.17° lead to the predominance of one kind of stripes, which are aligned in the off-orientation direction. On the other hand, the population of the two kinds of stripes are nearly equal in the layer grown on substrates without off-orientation. The crystalline quality of the former is significantly improved, as normalized minimum yields in the ion channeling analysis of the former are more than 27% smaller than that of the latter.