Method for controlled formation of the resistive switching material in a resistive switching device and device obtained thereof
View Patent ↗The present disclosure provides a method for controlled formation of the resistive switching layer in a resistive switching device. The method comprises providing a substrate ( 2 ) comprising the bottom electrode ( 10 ), providing on the substrate a dielectric layer ( 4 ) comprising a recess ( 7 ) containing the metal for forming the resistive layer ( 11 ), providing on the substrate a dielectric layer ( 5 ) comprising an opening ( 8 ) exposing the metal of the recess, and forming the resistive layer in the recess and in the opening.
1. A method for manufacturing a resistive switching device, comprising:
providing a substrate comprising a first electrode;
forming on the substrate a first dielectric layer;
etching the first dielectric layer to form a first trench;
depositing in the first trench a first metal;
forming on the first dielectric layer a second dielectric layer;
etching the second dielectric layer to form a second trench exposing at least a portion of the first metal; and
forming from the first metal and not from the first electrode a resistive switching material in at least a portion of the first trench and at least a portion of the second trench.
2. The method of claim 1 , wherein forming the resistive switching material comprises forming from a volume of the first metal a volume of the resistive switching material, wherein the volume of the resistive switching material is related to the volume of the first metal by a predefined volume expansion coefficient.
3. The method of claim 2 , further comprising:
selecting a volume of the first trench and a volume of the second trench based at least in part on the volume of the first metal and the predefined volume expansion coefficient.
4. The method of claim 1 , further comprising:
forming on the second dielectric layer a third dielectric layer;
etching the third dielectric layer to form a third trench; and
forming a second electrode in at least the third trench.
5. The method of claim 4 , wherein forming the resistive switching material in at least a portion of the second trench comprises forming the resistive switching material in substantially all of the second trench.
6. The method of claim 1 , wherein providing the substrate comprising the first electrode comprises:
forming on the substrate a substrate-dielectric layer;
etching the substrate-dielectric layer to form a substrate-trench; and
depositing in the substrate-trench an electrode metal, thereby forming a first metal pattern comprising the first electrode.
7. The method of claim 1 , wherein the resistive switching material comprises a charge transfer complex comprising an electron donor and an electron acceptor.
8. The method of claim 7 , wherein the resistive switching material is an organic compound having a pi electron system.
9. The method of claim 8 , wherein the organic compound is provided by tetracyanoquinodimethane (TCNQ) or by a derivative of TCNQ.
10. The method of claim 9 , wherein the electron donor is provided by the first metal, wherein the first metal is selected from the group consisting of copper, silver, and potassium.
11. The method of claim 1 , wherein the resistive switching material is a binary metal oxide.
12. The method of claim 11 , wherein the first electrode comprises copper, and the binary metal oxide is a cuprous metal oxide.
13. The method of claim 1 , wherein the first electrode comprises an electrode metal that differs from the first metal.
14. The method of claim 1 , wherein the resistive switching device is a non-volatile memory device.
15. The method of claim 4 , wherein the first electrode is in electrical contact with the second electrode via the resistive switching material.
16. The method of claim 4 , wherein forming the second electrode in the third trench comprises:
depositing a third metal; and
removing at least a portion of any of the third metal outside the third trench.
17. The method of claim 1 , further comprising:
prior to depositing the first metal, forming in the first trench a barrier layer.