A method of detaching two substrates at the embrittlement zone situated at a given depth of one of the two substrates. The method includes a separation annealing step implemented in a furnace, wherein the annealing includes a first phase during which the temperature changes along an upgrade allowing a high temperature to be reached and annealing at this high temperature to be stabilized, and a second phase during which the temperature changes along a downgrade, at the end of which the furnace is opened to unload the substrates from the furnace. The second phase is regulated so as to minimize temperature inhomogeneities such as cleavage defects at the detached surfaces of the substrates when the furnace is opened.