The present disclosure concerns a method of detaching a layer to be detached from a donor substrate, comprising the following steps: a) assembling the donor substrate and a porous substrate, b) application of a treatment of chemical modification of the crystallites, the chemical modification being adapted to generate a variation of the volume of the crystallites, the volume variation generates deformation in compression or in tension of the porous substrate, the deformation in compression or in tension generates a stress in tension or in compression in the donor substrate, which causes fracture in a fracture plane, the fracture plane delimiting the layer to be detached, the stress leading to the detachment of the layer to be detached from the donor substrate.