Abstract: A process for the production of a photovoltaic material or device based on monocrystalline silicon adapted to absorb particularly infrared radiation. A wafer, a slice or a chip region of monocrystalline silicon having a diffusion length greater than the path of the minorities in the base or greater than the total thickness of the wafer, slice or chip region, is obtained. Then the rear surface of the wafer, slice or chip region, not adapted to be exposed to photovoltaic radiation, is treated so as to create a rear field as well as zones or points of electrical contact. Then the forward surface is treated so as to form a thin surface emitter layer, a P-N junction of shallow depth, as well as a continuous flat substructure strongly doped, embedded in the emitter, of very small thickness and provided with several crystalline and electrical interfaces, particularly two interfaces of the L-H type and two crystalline hetero-interfaces.