A method for manufacturing a PCRAM memory includes forming in a first dielectric layer arranged on a substrate, which includes bottom electrodes, a first rectilinear trench opening onto the set of electrodes; depositing a first active layer in the first trench, such that the first active layer is in electrical contact with the electrodes; covering the first active layer with a second dielectric layer; etching, in the second and second dielectric layers and the first active layer, additional rectilinear trenches oriented perpendicularly to the first trench, to obtain a group of memory devices each including a portion of the first active layer in electrical contact with one of the electrodes; filling the additional trenches with a sacrificial dielectric material; performing an anisotropic etching of the sacrificial material to expose a side surface of each portion of the first active layer; and covering the side surface with a second active layer.