Electrode for a metal-insulator-metal structure, capacitor of metal-insulator-metal type, and method for fabricating one such electrode and one such capacitor

Patent metadata

Field	Value
Publication number	US-10319806-B2
Application number	US-201615220869-A
Country	US
Kind code	B2
Filing date	Jul 27, 2016
Priority date	Jul 28, 2015
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

The electrode is used to fabricate a capacitor of Metal-Insulator-Metal type.

First claim

The invention claimed is:

1. Electrode for a structure of Metal-Insulator-Metal type formed on a substrate by a stack successively comprising, from the substrate, an adhesion layer comprising a layer made from TiO 2 , a gold layer in direct contact with the adhesion layer, a barrier layer made from electrically conducting oxide in direct contact with the gold layer, and a platinum layer in direct contact with the barrier layer.

2. Electrode according to claim 1 , wherein the barrier layer is made from RuO 2 .

3. Electrode according to claim 2 , wherein the barrier layer has a thickness greater than or equal to 15 nm.

4. Electrode according to claim 3 , wherein the barrier layer has a thickness greater than or equal to 80 nm.

5. Electrode according to claim 1 , wherein the adhesion layer is a TiO 2 /metal bilayer, the metal being chosen from titanium, chromium, or tantalum, and the gold layer is in direct contact with the layer made from TiO 2 .

6. Electrode according to claim 1 , wherein the platinum layer has a thickness of about 100 nm and the gold layer has a thickness ranging from 1 μm to 2 μm.

7. Method for fabricating the electrode according to claim 1 , comprising successively:
providing a substrate covered by an adhesion layer made from titanium dioxide,
forming an electrode on the adhesion layer, the electrode being formed by successive depositions of a gold layer, a barrier layer made from electrically conducting oxide and a platinum layer, the electrically conducting oxide being a noble metal oxide.

8. Method for fabricating a capacitor comprising successively:
fabricating an electrode according to claim 1 as a first electrode,
forming a layer of perovskite type dielectric material on the platinum layer of the first electrode,
performing heat treatment at a temperature greater than or equal to 700° C. under oxygen so as to crystallize the dielectric material,
forming a second electrode on the crystallized dielectric material layer.

9. Method according to claim 8 , wherein the heat treatment temperature is greater than or equal to 850° C.

10. Electrode according to claim 5 , wherein the adhesion layer is a TiO 2 /titanium bilayer.

11. Electrode according to claim 1 , wherein the gold layer has a thickness ranging from 1 μm to 2 μm.

12. Method according to claim 7 , wherein the layer made of TiO 2 is formed by oxidation of the layer made of Ti metal.

13. Electrode according to claim 1 , wherein the adhesion layer completely separates the gold layer and the substrate.

14. Electrode according to claim 1 , wherein the layer made of TiO 2 completely separates the Ti metal layer and the gold layer.

15. Capacitor of Metal-Insulator-Metal type comprising:
a first electrode formed by a stack successively comprising a gold layer in direct contact with the adhesion layer, a barrier layer made from electrically conducting oxide in direct contact with the gold layer, and a platinum layer in direct contact with the barrier layer, the electrically conducting oxide being a noble metal oxide,
a second electrode,
a layer of perovskite type dielectric material arranged between the first electrode and the second electrode.

16. Capacitor according to claim 15 , wherein the barrier layer is made from RuO 2 with a thickness greater than or equal to 15 nm.

17. Capacitor according to claim 15 , comprising a substrate and wherein the gold layer is separated from the substrate by an adhesive layer made from titanium dioxide.

18. Capacitor according to claim 15 , wherein the perovskite type dielectric material is selected from a group consisting of Pb[Zr x Ti 1-x ]O 3 , SrTiO 3 , BaTiO 3 , and Ba[Sr x Ti 1-x ]O 3 .

19. Electrode for a structure of Metal-Insulator-Metal type formed on a substrate by a stack successively comprising, from the substrate, a gold layer, a barrier layer made from RuO 2 in direct contact with the gold layer and a platinum layer in direct contact with the barrier layer and wherein the barrier layer has a thickness greater than or equal to 15 nm so as to block diffusion of gold and platinum.

Assignees

• Commissariat Energie Atomique
• St Microelectronics Crolles 2 Sas

Inventors

• Rodriguez Guillaume
• Halimaoui Aomar
• Ortiz Laurent

Classifications

• H01L28/75 Primary

  Electricity · mapped topic

• H01L28/56

  Electricity · mapped topic

• H01L27/10805

  Electricity · mapped topic

• H01L28/57

  Electricity · mapped topic

• H01L28/65

  Electricity · mapped topic