A method for removing the growth substrate of a circuit of electromagnetic radiation detection, especially in the infrared or visible range, said detection circuit including a layer of detection of said radiation made of Hg(1-x)CdxTe obtained by liquid or vapor phase epitaxy or by molecular beam epitaxy, said detection circuit being hybridized on a read circuit. The method includes submitting the growth substrate to a mechanical or chem.-mech. polishing step or to a chemical etch step to decrease its thickness, all the way to an interface area between the material of the detection circuit and the growth substrate; and submitting the interface thus obtained to an iodine treatment.