Semiconductor structure and method for forming the same

Abstract

A semiconductor structure is provided. The semiconductor structure includes a substrate, a plurality of word line structures disposed on the substrate, and an insulating layer covering each word line structure. Each word line structure includes a conductive layer disposed at the lower part of the word line structure, a filling layer disposed at the upper part of the word line, and a barrier layer surrounding the filling layer. The barrier layer is a hydrogen-rich dielectric layer.

Claims

1. A semiconductor structure, comprising: One substrate; Multiple character line structures are disposed in the substrate. Each character line structure includes: a conductive layer disposed at the lower part of the character line structure; a filling layer disposed at the upper part of the character line structure; a barrier layer surrounding the filling layer, wherein the barrier layer is a hydrogen-rich dielectric layer; and an insulating layer covering each of the character line structures.

2. The semiconductor structure as claimed in claim 1, wherein the barrier layer is disposed on the sidewall and bottom of a portion of the fill layer.

3. The semiconductor structure as claimed in claim 1, wherein the top surface of the barrier layer is lower than the top surface of the fill layer.

4. The semiconductor structure as described in claim 1, further comprising: A first cover layer is disposed on the substrate; And a second cover layer disposed on the first cover layer.

5. The semiconductor structure as described in claim 4, wherein the second capping layer is another hydrogen-rich dielectric layer.

6. The semiconductor structure as claimed in claim 4, wherein the second capping layer and the barrier layer have different hydrogen ratios.

7. The semiconductor structure as described in claim 4, wherein the second capping layer is the hydrogen-rich dielectric layer.

8. The semiconductor structure as claimed in claim 4, wherein the second capping layer and the barrier layer have the same hydrogen ratio.

9. The semiconductor structure as described in claim 4, wherein the second capping layer comprises: A main body is disposed on the first cover layer; an extension extends from the bottom surface of the main body onto a portion of the sidewall of the filler layer and contacts the barrier layer.

10. The semiconductor structure as claimed in claim 9, wherein the bottom surface of the extension is lower than the top surface of the filling layer.

11. The semiconductor structure as claimed in claim 9, wherein the extension has an air gap therein.

12. The semiconductor structure as described in claim 4, further comprising: A third cover layer is disposed on the second cover layer.

13. The semiconductor structure as described in claim 12, wherein the third capping layer is another hydrogen-rich dielectric layer.

14. The semiconductor structure as claimed in claim 12, wherein the third capping layer has a different hydrogen ratio than the second capping layer.

15. The semiconductor structure as claimed in claim 12, wherein the third capping layer and the barrier layer have the same hydrogen ratio as the second capping layer.

16. The semiconductor structure as claimed in claim 1, wherein the conductive layer comprises: A metal layer is disposed at the bottom of the conductive layer; And a semiconductor layer disposed on the metal layer.

17. The semiconductor structure as described in claim 16, wherein the conductive layer further comprises: A first barrier layer surrounds the metal layer; And a second barrier layer is disposed between the metal layer and the semiconductor layer.

18. A method for forming a semiconductor structure, comprising: Provide a substrate; And forming a character line structure in the substrate, wherein forming the character line structure includes: forming a conductive layer in the lower part of the character line structure; And forming a filling layer and a barrier layer surrounding the filling layer on the conductive layer, wherein the barrier layer is a hydrogen-rich dielectric layer.

19. A method for forming a semiconductor structure as described in claim 18, wherein forming the barrier layer and the fill layer comprises: A barrier material layer is compliantly deposited on the conductive layer and the substrate; A filler material layer is compliantly deposited on the barrier material layer; Remove excess of the barrier material layer and the filler material layer to create a recess in the barrier layer.

20. The method for forming a semiconductor structure as described in claim 18 further includes: Before forming the character line structure, an insulating layer is formed in the substrate; A first capping layer is formed on the top surface of the insulating layer and the top surface of the substrate; and after forming the character line structure, a second capping layer and a third capping layer are sequentially formed on the barrier layer and the filler layer.

Images