A method for determining a suitable implanting energy of at least two atomic species in a donor substrate to create a weakened zone defining a monocrystalline semiconductor layer to be transferred onto a receiver substrate, comprises the following steps:(i) forming a dielectric layer on at least one of the donor substrate and the receiver substrate;(ii) co-implanting the species in the donor substrate;(iii) bonding the donor substrate on the receiver substrate;(iv) detaching the donor substrate along the weakened zone to transfer the monocrystalline semiconductor layer and recover the remainder of the donor substrate;(v) inspecting the peripheral crown of the remainder of the donor substrate, or of the receiver substrate on which the monocrystalline semiconductor layer was transferred at step (iv);(vi) if the crown exhibits zones transferred onto the receiver substrate, determining the fact that the implanting energy at step (ii) is too high;(vii) if said the crown does not exhibit zones transferred onto the receiver substrate, determining the fact that the implanting energy at step (ii) is suitable.