Dislocation structures of interfaces between bonded (001) Si wafers with co-existing low-angle twist and tilt misorientations were studied by transmission electron microscopy. At dominating twist, a square screw dislocation network accommodates the twist, and interacts with steps at the interface, forming 60-degree dislocations. As the step density, i.e., the tilt angle, increases relative to the twist angle, the density of so-called zigzag reactions increases. Finally, hexagonal dislocation meshes dominate the dislocation configuration. It was found that the plan-view observations give the crystallographic relations accurately. The structures of the dislocation configurations were analyzed using Bollmann's dualistic representation. The rotation axes and angles were determined. (C) 2004 Kluwer Academic Publishers.