Abstract: The field of the invention is that of integrated optical emission devices comprising a laser emission section and a section for modulating the optical power emitted by the laser, also known as ILM devices, the acronym standing for Integrated Laser Modulator. The invention is aimed at an ILM device comprising a laser section and a modulation section produced in a common structure of P.I.N type, the said structure successively comprising a substrate produced from n-doped semi-conductor material, a buried active zone, a p-doped vertical confinement layer and a semi-insulating lateral confinement layer, the part of the structure belonging to the laser section comprising a blocking layer produced from n-doped semi-conductor material disposed between the semi-insulating lateral confinement layer and the vertical confinement layer so as to reduce the leakage current existing between the said layers. The performance and the reliability of the final device is thus improved.