A method for separating a structure from a substrate using electromagnetic radiations within a spectral range, with the separation method comprising the steps of: a) providing the substrate, with the substrate being transparent in said spectral range, b) forming at least one separating layer on the substrate, with the spectral range of the electromagnetic radiations being tailored so that the separating layer(s) is/are absorbent in said spectral range, b1) forming a thermal barrier layer on the separating layer (s), with the spectral range of the electromagnetic radiations being tailored so that the thermal barrier layer is transparent in said spectral range, c) forming the structure to be separated on the thermal barrier layer, d) exposing the separating layer(s) to the electromagnetic radiations via the substrate for an exposure time at a given power density so that the separating layer(s) decompose(s) under the effect of the heat resulting from the absorption of said electromagnetic radiations, with the separation method being characterized in that the electromagnetic radiations are electromagnetic pulses; and in that the exposure time and the thickness of the thermal barrier layer, noted E1: - are tailored so that the temperature of the structure to be separated remains below a threshold for the whole exposure time beyond which defects are likely to appear in said structure, - satisfy the following relationship: E 1 ≥ 2 D 1 τ; where D 1 is the thermal diffusion coefficient of the thermal barrier layer, τ is the duration of an electromagnetic pulse. a) providing the substrate, with the substrate being transparent in said spectral range, b) forming at least one separating layer on the substrate, with the spectral range of the electromagnetic radiations being tailored so that the separating layer(s) is/are absorbent in said spectral range, b1) forming a thermal barrier layer on the separating layer (s), with the spectral range of the electromagnetic radiations being tailored so that the thermal barrier layer is transparent in said spectral range, c) forming the structure to be separated on the thermal barrier layer, d) exposing the separating layer(s) to the electromagnetic radiations via the substrate for an exposure time at a given power density so that the separating layer(s) decompose(s) under the effect of the heat resulting from the absorption of said electromagnetic radiations, with the separation method being characterized in that the electromagnetic radiations are electromagnetic pulses; and in that the exposure time and the thickness of the thermal barrier layer, noted E1: - are tailored so that the temperature of the structure to be separated remains below a threshold for the whole exposure time beyond which defects are likely to appear in said structure, - satisfy the following relationship: E 1 ≥ 2 D 1 τ; where D 1 is the thermal diffusion coefficient of the thermal barrier layer, τ is the duration of an electromagnetic pulse. - are tailored so that the temperature of the structure to be separated remains below a threshold for the whole exposure time beyond which defects are likely to appear in said structure, - satisfy the following relationship: E 1 ≥ 2 D 1 τ; where D 1 is the thermal diffusion coefficient of the thermal barrier layer, τ is the duration of an electromagnetic pulse.