Regensburg 1998 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

HL: Halbleiterphysik

HL 2: Poster I

HL 2.131: Poster

Monday, March 23, 1998, 10:30–19:00, A

Influence of the misorientation on the interface structure of wafer–bonded GaAs — •A. Klimashov, A. Trampert, K.-J. Friedland, and K. H. Ploog — Paul–Drude–Institut für Festkörper-
elektronik, Hausvogteiplatz 5–7, D-10117 Berlin

Epi-ready wafers of GaAs(001) were bonded under low pressure with a temperature treatment of 700 ^∘ C in nitrogen atmosphere. Different low-angle twist boundaries were realized by rotating the GaAs wafers against each other arond the [001] axis before the bonding process is started. The structure of the resulting interfaces was investigated by scanning and transmission electron microscopy techniques. Cross-sectional TEM images reveal a nearly perfectly bonded interface without the presence of a homogeneous interlayer. Only small nano-sized isolated precipitates were detected along the boundary plane which were determined as amorphous oxid particles, sporadically Ga- and As-rich crystallites were also identified. The degree of misorientation influences not only the distance between the screw dislocations in the perfectly bonded interfacial regions, but also the shape and the density of the precipitates. We discuss this result taking into account that there is a correlation between the formation of the precipitates and the generation of screw dislocations. This behaviour may help to find the optimum for the perfect bonded interface.