X-ray studies of silicon bonded interfaces.

The interface between two fusion-bonded silicon wafers has been investigated by synchrotron X-ray diffraction at the ESRF and HASYLAB,in close collaboration with the X-ray diffraction experts at Risø National Laboratory. The objective of this research is to study the interface structure and find applications for the unique nanostructures that occur at the interface. The fusion-bonded wafers were prepared with different twist angles between the crystals,leading to a highly ordered twist-boundary. Superstructure reflections due to the resulting regular network of dislocations at the interface were observed, and a correlation between the intensity and width of these reflections and the twist angle of the wafers has been investigated.