Metal insulator metal (MIM) capacitor structure

Patent metadata

Field	Value
Publication number	US-9252204-B2
Application number	US-201113233752-A
Country	US
Kind code	B2
Filing date	Sep 15, 2011
Priority date	Sep 15, 2011
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A MIM capacitor includes a dielectric cap that enhances performance and reduces damage to MIM insulators during manufacture. A cavity is formed in an insulative substrate, such as a back end of line dielectric layer, and a first metal layer and an insulator layer are conformally deposited. A second metal layer may be deposited conformally and/or to fill a remaining portion of the cavity. The dielectric cap may be an extra layer of insulative material deposited at ends of the insulator at an opening of the cavity and may also be formed as part of the insulator layer.

First claim

What is claimed is:

1. A MIM capacitor structure comprising:
an insulative substrate;
a first cavity formed in the insulative substrate;
a first metal layer conformally deposited in the first cavity;
an insulator layer conformally deposited on the first metal layer;
a second metal layer deposited directly on the insulator layer; and
an enlarged, relative to the insulator layer, dielectric cap of the insulator layer, at least one top surface of the dielectric cap being substantially flush with at least one top surface of the second metal layer, and an entirety of the insulator layer being below the dielectric cap and the at least one top surface of the second metal layer, and wherein the at least one top surface of the dielectric cap and the at least one top surface of the second metal layer are substantially flush with a top surface of a layer in which the dielectric cap is formed.

2. The structure of claim 1 , wherein the wherein the dielectric cap contacts the second metal layer and leaves at least a portion of a top surface of the second metal layer exposed.

3. The structure of claim 2 , wherein the dielectric cap contacts the first metal layer and leaves at least a portion of a top surface of the first metal layer.

4. The structure of claim 2 , wherein each of the first contact and the second contact are electrically connected to a respective one of the first metal layer and the second metal layer at the surface of the insulative substrate at the opening of the first cavity.

5. The structure of claim 1 , wherein the dielectric cap includes an extension of the insulator layer along a surface of the insulative substrate that is substantially perpendicular to a wall of the first cavity.

6. The structure of claim 1 , wherein the insulator layer is formed from a first dielectric material with an end surface substantially parallel to a top surface of the insulative substrate, and the dielectric cap includes a second dielectric material deposited at the end surface of the insulator layer.

7. The structure of claim 1 , wherein the first metal layer includes an extension along a top surface of the insulative substrate.

8. The structure of claim 1 , wherein the second metal layer includes an extension substantially parallel to a top surface of the insulative substrate.

9. The structure of claim 1 , wherein the dielectric cap is formed proximate a top surface of the insulative substrate and overlies at least a portion of the first metal layer, and at least a portion of the second metal layer is not covered by the dielectric cap.

10. The structure of claim 1 , further comprising a cover layer formed on the insulative substrate and covering substantially all exposed surfaces of the first metal layer, the insulator layer, and the second metal layer, the cover layer being formed from an insulative material.

11. The structure of claim 10 , wherein the dielectric cap is at least partly between the first and second metal layers and is at least partly between the cover layer and at least part of at least one side surface of the second metal layer.

12. A MIM capacitor structure comprising:
an insulative substrate having a top surface and a bottom surface;
a first cavity formed in the insulative substrate and extending from the top surface of the insulative substrate toward the bottom surface of the insulative substrate;
a first metal layer conformally deposited in the first cavity;
an insulator layer conformally deposited on the first metal layer;
a second metal layer deposited directly on the insulator layer;
an enlarged, relative to the insulator layer, dielectric cap of the insulator layer at least partly between the first and second metal layers, and an entirety of the insulator layer being below the dielectric cap and at least one top surface of the second metal layer; and
a cover layer formed from an insulative material and that contacts and substantially covers otherwise exposed portions of the insulative substrate, at least a portion of the dielectric cap, and at least a portion of the second metal layer, and wherein the insulator layer ends below the top surface of the insulative substrate, the dielectric cap covers and extends from ends of the insulator layer, and a top surface of the dielectric cap is substantially flush with the top surface of the insulative substrate.

13. The structure of claim 12 , wherein at least a portion of the dielectric cap is between the second metal layer and the cover layer.

14. The structure of claim 12 , wherein the at least a portion of the dielectric cap is in contact with and lies between the insulator layer and the cover layer.

15. The structure of claim 12 , wherein the dielectric cap overlies and contacts at least a portion of the first metal layer and covers and contacts at least one side surface of the second metal layer such that at least a portion of the dielectric cap lies between the at least one side surface and the cover layer.

16. The structure of claim 12 , wherein the dielectric cap is formed from a different layer of material than either of the insulator layer or the cover layer.

17. The structure of claim 12 , wherein at least a portion of a top surface of the second metal layer remains uncovered by the dielectric cap.

18. The structure of claim 12 , wherein at least a portion of a top surface of the first metal layer remains uncovered by the dielectric cap.

19. The structure of claim 12 , wherein top surfaces of at least the second metal layer, and the dielectric cap are substantially flush with at least one of each other and the top surface of the insulative substrate.

Assignees

• Adkisson James W
• Candra Panglijen
• Ogg Kevin N
• Stamper Anthony K
• Globalfoundries Inc

Inventors

• Adkisson James W
• Candra Panglijen
• Ogg Kevin N
• Stamper Anthony K

Classifications

• H10D1/716 Primary

  having vertical extensions · CPC title

• H01L28/90 Primary

  Electricity · mapped topic