Interface induced diffusion

Interface induced diffusion had been identified in a thin film system damaged by electron bombardment. This new phenomenon was observed in Al2O3 (some nm thick)/Si substrate system, which was subjected to low energy (5 keV) electron bombardment producing defects in the Al2O3 layer. The defects produced partially relaxed. The rate of relaxation is, however, was different in the vicinity of the interface and in the bulk parts of the Al2O3 layer. This difference creates an oxygen concentration gradient and consequently oxygen diffusion, resulting in an altered layer which grows from the Al2O3/Si substrate interface. The relative rate of the diffusion and relaxation is strongly temperature dependent, resulting in various altered layer compositions, SiO2 (at room temperature), Al2O3+AlOx+Si (at 500 degrees C), Al2O3+Si (at 700 degrees C), as the temperature during irradiation varies. Utilizing this finding it is possible to produce area selective interface patterning.

Automated summary

The study revealed that interface induced diffusion creates an oxygen concentration gradient and results in oxygen diffusion, leading to the growth of an altered layer from the Al2O3/Si substrate interface. The rate of diffusion and relaxation is strongly temperature dependent, resulting in different altered layer compositions at different temperatures.