A method for structuring the front face of a substrate by producing at least one pattern on the front face of the substrate , the method comprising at least the following steps: - providing a substrate having a front face surmounted at least by a masking layer comprising carbon atoms, - defining at least one mask pattern in the masking layer so that the masking layer comprises adjacent regions with different height levels, - performing an ion implantation of the substrate through said front face and at least upright of the mask pattern , so as to form at least one first area modified by implantation and at least one second area not modified by the implantation or less modified than the first area , the implantation conditions being chosen so that after implantation the at least one first area has a resistivity p1 less than the resistivity p2 of the at least one second area , - removing the masking layer so that the front face of the substrate is exposed, characterised in that it then comprises at least the following successive steps: - after the implantation step, immersing the substrate in an electrolyte so that the front face of the exposed substrate is completely in contact with the electrolyte , - removing the at least one first area selectively to the at least one second area so as to form on the front face of the substrate at least one pattern the geometry of which depends on the mask pattern , the removal step comprising at least applying an electrochemistry step to the substrate for causing a porosification of the at least one first area selectively to the at least one second area , the removal step being carried out so that, at least during the electrochemistry step, at least one rear face of the substrate opposite the front face has charge carriers. and characterised in that - during the implantation step, the substrate is surmounted by a buffer layer located between the front face of the substrate and the masking layer , the buffer layer being shaped so as to trap the carbon atoms which would be torn from the masking layer during said ion implantation. - providing a substrate having a front face surmounted at least by a masking layer comprising carbon atoms, - defining at least one mask pattern in the masking layer so that the masking layer comprises adjacent regions with different height levels, - performing an ion implantation of the substrate through said front face and at least upright of the mask pattern , so as to form at least one first area modified by implantation and at least one second area not modified by the implantation or less modified than the first area , the implantation conditions being chosen so that after implantation the at least one first area has a resistivity p1 less than the resistivity p2 of the at least one second area , - removing the masking layer so that the front face of the substrate is exposed, - after the implantation step, immersing the substrate in an electrolyte so that the front face of the exposed substrate is completely in contact with the electrolyte , - removing the at least one first area selectively to the at least one second area so as to form on the front face of the substrate at least one pattern the geometry of which depends on the mask pattern , the removal step comprising at least applying an electrochemistry step to the substrate for causing a porosification of the at least one first area selectively to the at least one second area , the removal step being carried out so that, at least during the electrochemistry step, at least one rear face of the substrate opposite the front face has charge carriers. and characterised in that - during the implantation step, the substrate is surmounted by a buffer layer located between the front face of the substrate and the masking layer , the buffer layer being shaped so as to trap the carbon atoms which would be torn from the masking layer during said ion implantation. <EOS>