A technique for fabricating an epitaxial component layer sequence based on a first III/V compound semiconductor material system with a first group V element on a substrate or a buffer layer, which comprises a material based on a second III/V compound semiconductor material system with a second group V element, which is different from the first group V element. At least one layer sequence with a first and a second III/V compound semiconductor material layer is applied to the substrate or to the buffer layer before the application of the epitaxial component layer sequence, the first and second III/V compound semiconductor material layers having different compositions from one another and containing both the first and the second group V elements.