Method for transfer of a useful layer

A method for transfer of a useful layer on a supporting substrate, comprising the successive steps of:

• a) providing a donor substrate comprising a first surface;
• b) smoothing the first surface of the donor substrate until a reconstructed surface topology is obtained;
• c) forming a first dielectric film on the smoothed first surface of the donor substrate, in such a way that the first dielectric film has a surface that preserves the reconstructed surface topology;
• d) implanting gaseous species in the donor substrate, through the first dielectric film, so as to form an embrittlement zone, the useful layer being delimited by the embrittlement zone and by the first surface of the donor substrate;
• e) assembling the donor substrate on the supporting substrate by direct adhesion;
• and
• f) splitting the donor substrate along the embrittlement zone so as to expose the useful layer.