| 摘要 |
The invention relates to a laminated layer structure that includes a substrate and a stack of a plurality of layers of a material that includes at least two compounds A and B, wherein compound A has a crystalline structure being sufficient to allow a homo- or heteroepitaxial growth of compound A on the substrate, and wherein at least a part of the layers of the stack have a gradient composition A<SUB>x</SUB>B<SUB>(1-xg)</SUB>, with x being a composition parameter within the range of 0 and 1 and with the composition parameter (1-x<SUB>g</SUB>) increasing gradually, in particular linearly, over the thickness of the corresponding layer. In order to improve the quality of the laminated layer structure with respect to the surface roughness and dislocation density, the composition parameter at the interface between the layer in the stack with the gradient composition and the subsequent layer in the stack is chosen to be smaller than the composition parameter (1-x<SUB>g</SUB>) of the layer with a gradient composition. The invention also relates to a method to fabricate such a laminated layer structure.
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