TEM, AES and XPS Studies of Si Layer on Buried SiO2 Layer Formed by High-Dose Oxygen Ion-Implantation

Depth distributions of crystallographic and chemical properties in oxygen ion-implanted Si layers have been studied by TEM, AES and XPS. Oxygen ions (16O+) were implanted into (100)-Si wafers at 150 keV to a dose of 1.2×1018/cm2. The dose rate was about 15 µA/cm2. The implanted oxygen forms a buried SiO2 layer after annealing. The Si layer on this buried SiO2 layer is not completely amorphized by implantation, and changes after annealing to a single crystal Si layer at the surface region and a deeper polycrystalline Si layer. A twin layer is formed at the interface region between these two layers. The polycrystalline Si layer consists of a mixture of Si and SiO2.