3D capacitor and method of manufacturing same

• US 10,283,613 B2
• Filed: 02/08/2018
• Issued: 05/07/2019
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Liu, Chi-Wen, Wang, Chao-Hsiung
• Primary Examiner(s): Jahan, Bilkis
• Application Number:
  US15/891,959
• Publication Number:
  US 20180175164A1
• Time in Patent Office: 453 Days
• Field of Search: None
• CPC Class Codes: H01L 28/92 made by patterning layers, e.g. by etching conductive layers
• CPC Class Codes: H01L 29/66181 Conductor-insulator-semiconductor capacitors, e.g. trench capacitors
• CPC Class Codes: H01L 29/94 Metal-insulator-semiconductors, e.g. MOS
• CPC Class Codes: H01L 29/945 Trench capacitors

Abstract

A three-dimensional (3D) capacitor includes a semiconductor substrate; a fin structure including one or more fins formed on the semiconductor substrate; an insulator material formed between each of the one or more fins; a dielectric layer formed on a first portion of the fin structure; a first electrode formed on the dielectric layer; spacers formed on sidewalls of the first electrode; and a second electrode formed on a second portion of the fin structure. The first and second portions are different. The second electrode includes a surface that is in direct contact with a surface of the spacers.

Claims

1. A method of manufacturing a three-dimensional (3D) capacitor, comprising:

providing a substrate;

forming a fin structure including one or more fins on the substrate;

implanting the fin structure to form a low-resistance surface on the fin structure;

depositing an insulation material on the substrate and on the fin structure, the insulation material substantially filling a region between each of the one or more fins;

removing a portion of the insulation material from the region between each of the one or more fins such that a portion of each of the one or more fins is exposed;

forming a dielectric layer over each of the one or more fins;

forming a first electrode on a first portion of the fin structure; and

forming a second electrode on a second portion of the fin structure,

wherein the first and second portions are different, and

wherein the first and second electrodes are isolated one from the other.

2. The method of claim 1, wherein the implanting of the fin structure is performed before the depositing of the insulation material.

3. The method of claim 1, wherein the implanting of the fin structure is performed after the depositing of the insulation material and the removing of the portion of the insulation material.

4. The method of claim 1, wherein the first electrode is formed in direct contact with the low-resistance surface on the first portion of the fin structure.

5. The method of claim 1, wherein the implanting of the fin structure includes implanting boron, phosphorous, or arsenic into the fin structure.

6. The method of claim 1, before the removing of the portion of the insulation material, performing a planarizing process to the insulation material.

7. The method of claim 1, wherein the dielectric layer includes a high-k dielectric material.

8. A method of manufacturing a three-dimensional (3D) capacitor, comprising:

providing a substrate;

forming a fin structure including one or more fins on the substrate;

depositing an insulation material on the substrate and on the fin structure, the insulation material substantially filling a region between each of the one or more fins;

planarizing the insulation material;

removing a portion of the insulation material such that a portion of each of the one or more fins is exposed;

implanting the fin structure to form a low-resistance surface on the fin structure;

depositing a dielectric layer over each of the one or more fins and over the insulation material;

forming a first electrode over a first portion of the fin structure; and

forming a second electrode over a second portion of the fin structure,

wherein the first and second portions of the fin structure are different, and

wherein the first and second electrodes are isolated one from the other.

9. The method of claim 8, wherein the implanting is performed after forming the fin structure and before depositing the insulation material,

wherein forming the first electrode includes forming the first electrode such that the first electrode has direct contact with the low-resistance surface of the fin structure,

wherein forming the second electrode includes forming the second electrode on the dielectric layer such that the second electrode does not have direct contact with the low-resistance surface of the fin structure, and

wherein the first and second electrodes do not share a common fin.

10. The method of claim 8, wherein the implanting is performed after forming the fin structure and before depositing the insulation material,

wherein the first portion includes a first fin of the one or more fins of the fin structure,

wherein the second portion includes a second fin of the one or more fins of the fin structure, and

wherein the first and second fins are different fins.

11. The method of claim 8, wherein the implanting is performed after removing the portion of the insulation material,

wherein forming the first electrode includes forming the first electrode such that the first electrode has direct contact with the low-resistance surface of the fin structure, and

wherein forming the second electrode includes forming the second electrode on the dielectric layer such that the second electrode does not have direct contact with the low-resistance surface of the fin structure.

12. The method of claim 8, wherein the implanting is performed after removing the portion of the insulation material, further comprising:

forming spacers on sidewalls of the first electrode,

wherein the second electrode includes a surface that is in direct contact with a surface of the spacers.

13. The method of claim 12, wherein forming the first electrode includes forming the first electrode such that each of the one or more fins is traversed, and

wherein forming the second electrode includes forming the second electrode such that each of the one or more fins is traversed.

14. The method of claim 13, wherein forming the first electrode includes forming the first electrode directly on the dielectric layer and in the region between each of the one or more fins, and

wherein forming the second electrode includes forming the second electrode directly on the low-resistance surface of the fin structure and in the region between each of the one or more fins.

15. The method of claim 14, wherein forming the second electrode includes forming the second electrode directly on the insulation material in the region between each of the one or more fins.

16. A method of manufacturing a three-dimensional (3D) capacitor, comprising:

providing a substrate;

forming one or more fins on the substrate;

depositing an insulation material on the substrate and filling a region between each of the one or more fins;

etching back the insulation material such that a portion of each of the one or more fins is exposed;

after the etching back, implanting the one or more fins to form a low-resistance surface on the one or more fins;

after the implanting, forming a dielectric layer over each of the one or more fins above the insulation material;

forming a first electrode on a first subset of the one or more fins; and

forming a second electrode on a second subset of the one or more fins,

wherein the first and second subsets are different portions of same fins.

17. The method of claim 16, wherein the first and second electrodes are isolated from each other.

18. The method of claim 16, wherein the first electrode is formed in direct contact with the low-resistance surface on the first subset of the one or more fins.

19. The method of claim 18, wherein the second electrode is formed to be separate from the low-resistance surface by at least the dielectric layer.

20. The method of claim 16, further comprising:

forming a spacer between the first and second electrodes.