Gas phase epitaxy method, comprising the method step: - growing a III-V layer with a doping, which changes from a first type of conductivity to a second type of conductivity, on a surface of a substrate or a preceding layer in a reaction chamber from the gas phase from an epitaxy gas flow comprising a carrier gas, at least one first precursor for an element from the III main group and at least one second precursor for an element from the V main group, wherein the first conductivity type is p and the second conductivity type is n - on reaching a first growth height by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxy gas flow and with or without addition of a further precursor for a doping substance of the first conductivity type to the epitaxy gas flow a first doping start value of the first conductivity type is set, - subsequently the first doping start value through addition of a third mass flow of a third precursor for a doping substance of the second conductivity type to the epitaxy gas flow and/or through changing the ratio of the first mass flow to the second mass flow is abruptly reduced to a second doping start value of the first conductivity type or is set to a second doping start value (DA2 ∗) of the second conductivity type of at most 1·10 15 cm -3 and - subsequently through stepped or continuous increase in the mass flow of the third precursor and/or through stepped or continuous change in the ratio of the first mass flow to the second mass flow a doping of the III-V layer is changed over a transition region layer (Ü) with a growth height of at least 10 μm in steps or continuously until reaching a doping target value of the second conductivity type. - growing a III-V layer with a doping, which changes from a first type of conductivity to a second type of conductivity, on a surface of a substrate or a preceding layer in a reaction chamber from the gas phase from an epitaxy gas flow comprising a carrier gas, at least one first precursor for an element from the III main group and at least one second precursor for an element from the V main group, wherein - on reaching a first growth height by means of a ratio of a first mass flow of the first precursor to a second mass flow of the second precursor in the epitaxy gas flow and with or without addition of a further precursor for a doping substance of the first conductivity type to the epitaxy gas flow a first doping start value of the first conductivity type is set, - subsequently the first doping start value through addition of a third mass flow of a third precursor for a doping substance of the second conductivity type to the epitaxy gas flow and/or through changing the ratio of the first mass flow to the second mass flow is abruptly reduced to a second doping start value of the first conductivity type or is set to a second doping start value (DA2 ∗) of the second conductivity type of at most 1·10 15 cm -3 and - subsequently through stepped or continuous increase in the mass flow of the third precursor and/or through stepped or continuous change in the ratio of the first mass flow to the second mass flow a doping of the III-V layer is changed over a transition region layer (Ü) with a growth height of at least 10 μm in steps or continuously until reaching a doping target value of the second conductivity type.