Gate interface engineering with doped layer

Patent metadata

Field	Value
Publication number	US-11456178-B2
Application number	US-202117348081-A
Country	US
Kind code	B2
Filing date	Jun 15, 2021
Priority date	Jun 17, 2020
Publication date	Sep 27, 2022
Grant date	Sep 27, 2022

Abstract

Processing methods may be performed to produce semiconductor structures. The methods may include forming a silicon layer over a semiconductor substrate. The forming may include forming a silicon layer incorporating a dopant. The methods may include oxidizing a portion of the silicon layer while maintaining a portion of the silicon layer in contact with the semiconductor substrate. The oxidizing may drive a portion of the dopant through the silicon layer and into the semiconductor substrate.

First claim

The invention claimed is:

1. A method of forming a semiconductor structure, the method comprising:
forming a silicon layer over a semiconductor substrate, wherein the forming comprises:
forming a silicon layer incorporating a dopant; and

oxidizing a portion of the silicon layer, wherein the oxidizing drives a portion of the dopant through the silicon layer and into the semiconductor substrate.

2. The method of forming a semiconductor structure of claim 1 , wherein the silicon layer is formed by atomic-layer deposition or epitaxial growth.

3. The method of forming a semiconductor structure of claim 1 , wherein the dopant comprises one or more of nitrogen, phosphorus, or fluorine.

4. The method of forming a semiconductor structure of claim 1 , wherein the silicon layer is formed to a thickness of less than or about 5 nm.

5. The method of forming a semiconductor structure of claim 1 , wherein oxidizing a portion of the silicon layer forms a sacrificial oxide, the method further comprising:
removing the sacrificial oxide, wherein the removing includes an in-situ dry chemical process.

6. The method of forming a semiconductor structure of claim 5 , wherein the removing is performed in a first processing chamber, and wherein the method further comprises
forming an oxygen-containing material;
transferring the semiconductor substrate from the first processing chamber to a second processing chamber; and
forming a high-k dielectric material overlying the oxygen-containing material.

7. The method of forming a semiconductor structure of claim 6 , further comprising, prior to forming the high-k dielectric material, introducing reactive ligands on the oxygen-containing material with a nitrogen-containing precursor or an oxygen-containing precursor.

8. The method of forming a semiconductor structure of claim 7 , wherein the nitrogen-containing precursor comprises ammonia.

9. The method of forming a semiconductor structure of claim 6 , wherein the high-k dielectric material comprises at least one element selected from the group consisting of hafnium, zirconium, silicon, lanthanum, aluminum, titanium, and strontium.

10. The method of forming a semiconductor structure of claim 1 , wherein the method is performed in one or more processing chambers without exposing the semiconductor substrate to atmosphere.

11. The method of forming a semiconductor structure of claim 1 , wherein the silicon layer is formed epitaxially over the semiconductor substrate, and wherein the semiconductor substrate comprises silicon germanium.

12. The method of forming a semiconductor structure of claim 1 , wherein oxidizing a portion of the silicon layer forms a sacrificial oxide, wherein forming the sacrificial oxide comprises a first oxidation process, and wherein the method further comprises:
oxidizing the portion of the silicon layer in contact with the semiconductor substrate comprises a second oxidation process different from the first oxidation process.

13. The method of forming a semiconductor structure of claim 1 , wherein the oxidizing the portion of the silicon layer in contact with the semiconductor substrate comprises delivering a nitrogen-and-oxygen containing precursor to the semiconductor substrate.

14. The method of forming a semiconductor structure of claim 13 , wherein the oxidizing the portion of the silicon layer in contact with the semiconductor substrate occurs at a temperature of less than or about 750° C.

15. A method of forming a semiconductor structure, the method comprising:
removing oxide from a surface of a substrate contained in a semiconductor processing chamber, wherein the substrate comprises a silicon germanium fin;
forming a silicon layer over a semiconductor substrate, wherein the forming comprises:
forming a silicon layer incorporating nitrogen, fluorine, or phosphorus as a dopant; and

oxidizing the silicon layer to form a sacrificial oxide, wherein the oxidizing diffuses a portion of the dopant through the silicon layer and into the semiconductor substrate;
removing the sacrificial oxide;
delivering nitrous oxide to the substrate to form an oxygen-containing material;
pre-treating the oxygen-containing material by contacting the substrate with a nitrogen-containing precursor; and
forming a high-k dielectric material overlying the pre-treated oxygen-containing material.

16. The method of forming a semiconductor structure of claim 15 , wherein the removing includes an in-situ dry chemical process.

17. The method of forming a semiconductor structure of claim 16 , wherein the removing is performed in a first processing chamber, and wherein the method further comprises transferring the substrate from the first processing chamber to a second processing chamber prior to forming the high-k dielectric material.

18. The method of forming a semiconductor structure of claim 15 , wherein the silicon layer is formed by atomic-layer deposition or epitaxial growth, and wherein the silicon layer is formed to a thickness of less than or about 5 nm.

19. The method of forming a semiconductor structure of claim 15 , wherein forming the sacrificial oxide comprises delivering an oxygen-containing precursor and a hydrogen-containing precursor to the substrate to form an oxygen-containing material.

20. A method of forming a semiconductor structure, the method comprising:
removing a native oxide from a surface of a substrate contained in a semiconductor processing chamber, wherein the substrate comprises silicon germanium;
forming a silicon layer over a semiconductor substrate, wherein the forming comprises:
forming a silicon layer incorporating a dopant; and

oxidizing a portion of the silicon layer to form a sacrificial oxide while maintaining a portion of the silicon layer in contact with the semiconductor substrate, wherein the oxidizing drives a portion of the dopant through the silicon layer and into the semiconductor substrate; and
removing the sacrificial oxide.

Assignees

• Applied Materials Inc

Inventors

• Hung Steven C H
• Colombeau Benjamin
• Dube Abhishek
• Kung Sheng-Chin
• Liu Patricia M
• Bevan Malcolm J
• Swenberg Johanes F

Classifications

• H10P14/6308 Primary

  of Group IV semiconductors · CPC title

• H10P14/3411

  Silicon, silicon germanium or germanium · CPC title

• H10D64/0134

  with a treatment, e.g. annealing, after the formation of the insulator and before the formation of the conductor · CPC title

• H10D64/01352 Primary

  with sacrificial oxide · CPC title

• H10D64/01314

  the conductor comprising a layer of Ge, C or of compounds of Si, Ge or C contacting the insulator · CPC title