A method for manufacturing at least one elementary cell comprising a non-volatile resistive random-access memory mounted in series with a volatile selector device, said non-volatile resistive random-access memory comprising:
- an upper electrode of the resistive random-access memory,
- a lower electrode of the resistive random-access memory,
- a memory active layer made of a first active material,
- said non-volatile resistive random-access memory going from a high resistance state to a low resistance state by application of a threshold voltage between the upper electrode of the resistive random-access memory and the lower electrode of the resistive random-access memory, said selector device comprising:
- an upper electrode of the selector device,
- a lower electrode of the selector device,
- a selector active layer made of a second active material,
- said selector device going from a high resistance state to a low resistance state by application of a threshold voltage between the upper electrode of the selector device and the lower electrode of the selector device, said selector device returning to the high resistance state as soon as the current flowing through it or the voltage at the terminals of the upper electrode of the selector device and the lower electrode of the selector device returns respectively below a holding current or voltage, the method comprising the following steps:
- a step of conformal deposition of a conductor material layer of the lower electrode of the selector device on a substrate then of conformal deposition of a first dielectric material layer on the conductor material layer of the lower electrode of the selector device;
- a step of etching one or more trenches, the one or more trenches being parallel with each other, in the first dielectric material layer with stoppage on the conductor material layer of the lower electrode of the selector device;
- a step of conformal deposition of the selector active layer in order to cover each trench and the parts of the first dielectric material layer that have not been etched during the etching step, then of conformal deposition of a material layer of the one-piece conductor element on the selector active layer then of conformal deposition of a second dielectric layer on the material layer of the one-piece conductor element, in such a way that each trench is not filled;
- a step of anisotropic etching along a direction of the one or more trenches with stoppage on the conductor material layer of the lower electrode of the selector device at the bottom of the one or more trenches and with stoppage on the parts of the first dielectric material layer not having been etched during the etching step in order to obtain at least one one-piece conductor element;
- a step of filling with a third dielectric material layer so as to fill the one or more trenches;
- a step of lithography producing at least one lithographic trench along a direction perpendicular to the direction of the one or more trenches etched previously and in the plane of the third dielectric material layer, with stoppage on the substrate;
- a step of filling with a fourth dielectric material layer so as to fill the at least one lithographic trench;
- a step of planarization with stoppage on the parts of the first dielectric material layer not having been etched;
- a step of conformal deposition of a memory active layer then of conformal deposition of a conductor material layer of the upper electrode of the resistive random-access memory on the memory active layer.