Method for structuring a substrate (11) and comprising the following steps: —providing a device (100) comprising a light source (33), an optical system (2) for obtaining an outgoing light beam (7) spatially offset in relation to the incoming light beam (1), and capable of modifying this spatial offset, focusing means (9) for focusing the outgoing light beam (7), a substrate holder (59), a movement device (60) for generating a movement (41) between the outgoing light beam (7) and the substrate (11); —providing and placing the substrate (11) on the substrate holder (59); —etching the substrate with the focused outgoing light beam (7) having an angle of attack (107) greater than 1° for any spatial offset between outgoing light beam (7) and incoming light beam (1) imposed by the optical system (2).