Systems and methods for material breakthrough

• US 10,490,406 B2
• Filed: 04/10/2018
• Issued: 11/26/2019
• Est. Priority Date: 04/10/2018
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Pandit, Mandar B., Ling, Mang-Mang, Choi, Tom, Ingle, Nitin K.
• Primary Examiner(s): Blum, David S
• Application Number:
  US15/949,341
• Publication Number:
  US 20190311900A1
• Time in Patent Office: 595 Days
• Field of Search: 438703, 438594
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32733 Means for moving the material to be treated
• CPC Class Codes: H01L 21/0337 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 29/66545 using a dummy, i.e. replacement gate in a process wherein at least a part of the final gate is self aligned to the dummy gate

Abstract

Methods may be performed to limit footing, pitch walking, and other alignment issues. The methods may include forming a treatment gas plasma within a processing region of a semiconductor processing chamber. The methods may further include directing effluents of the treatment gas plasma towards a semiconductor substrate within the processing region of the semiconductor processing chamber, and anisotropically modifying a surface of a first material on the semiconductor substrate with the effluents of the treatment gas plasma. The methods may also include passivating a surface of a second material on the semiconductor substrate with the effluents of the treatment gas plasma. The methods may further include forming a remote fluorine-containing plasma to produce fluorine-containing plasma effluents, and flowing the fluorine-containing plasma effluents to the processing region of the semiconductor processing chamber. The methods may also include selectively removing the modified surface of the first material from the semiconductor substrate.

Claims

1. An etching method comprising:

forming a treatment gas plasma within a processing region of a semiconductor processing chamber;

modifying a surface of a first material on a semiconductor substrate within the processing region of the semiconductor processing chamber with effluents of the treatment gas plasma;

modifying a surface of a second material on the semiconductor substrate with the effluents of the treatment gas plasma;

forming a remote plasma from a fluorine-containing precursor to produce fluorine-containing plasma effluents;

flowing the fluorine-containing plasma effluents to the processing region of the semiconductor processing chamber;

flowing water vapor to the processing region of the semiconductor processing chamber; and

selectively removing the modified surface of the first material from the semiconductor substrate.

2. The etching method of claim 1, wherein a temperature of the semiconductor substrate is maintained between about 5°

C. and about 35°

C.

3. The etching method of claim 1, wherein the fluorine-containing plasma effluents are formed in a remote region of the semiconductor processing chamber fluidly coupled with, and physically separated from, the processing region of the semiconductor processing chamber.

4. The etching method of claim 1, wherein the fluorine-containing plasma effluents are produced by a capacitively-coupled plasma at a power level of less than or about 300 W.

5. The etching method of claim 1, wherein the first material comprises a spacer material including an oxide material, the second material comprises a hardmask material including a nitride material.

6. The etching method of claim 1, wherein the etching method has a selectivity of at least 7:

1 of the modified first material relative to the modified second material.

7. An etching method comprising:

forming a treatment gas plasma within a processing region of a semiconductor processing chamber;

modifying a surface of a first material on a semiconductor substrate within the processing region of the semiconductor processing chamber with effluents of the treatment gas plasma, wherein the semiconductor substrate further comprises a second material different from the first material;

forming a remote plasma from a fluorine-containing precursor to produce fluorine-containing plasma effluents;

flowing the fluorine-containing plasma effluents to the processing region of the semiconductor processing chamber;

flowing water vapor to the processing region of the semiconductor processing chamber; and

selectively removing the modified surface of the first material from the semiconductor substrate.

8. The etching method of claim 7, further comprising modifying a surface of the second material on the semiconductor substrate with the effluents of the treatment gas plasma.

9. The etching method of claim 7, further comprising adsorbing the water vapor at the surface of the first material.

10. The etching method of claim 7, wherein a temperature of the semiconductor substrate is maintained between about 5°

C. and about 35°

C.

11. The etching method of claim 7, wherein the fluorine-containing plasma effluents are formed in a remote region of the semiconductor processing chamber fluidly coupled with, and physically separated from, the processing region of the semiconductor processing chamber.

12. The etching method of claim 7, wherein the first material comprises a spacer material including an oxide material, the second material comprises a hardmask material including a nitride material.

13. The etching method of claim 7, wherein the etching method has a selectivity of at least 7:

1 of the modified first material relative to the modified second material.

14. An etching method comprising:

forming a treatment gas plasma within a processing region of a semiconductor processing chamber;

modifying a surface of a first material on a semiconductor substrate within the processing region of the semiconductor processing chamber with effluents of the treatment gas plasma;

modifying a surface of a second material on the semiconductor substrate with the effluents of the treatment gas plasma;

forming a remote plasma from a fluorine-containing precursor to produce fluorine-containing plasma effluents;

flowing the fluorine-containing plasma effluents to the processing region of the semiconductor processing chamber;

flowing water vapor to the processing region of the semiconductor processing chamber to combine with the fluorine-containing plasma effluents; and

selectively removing the modified surface of the first material from the semiconductor substrate.

15. The etching method of claim 14, wherein a temperature of the semiconductor substrate is maintained between about 0°

C. and about 50°

C.

16. The etching method of claim 14, wherein the fluorine-containing plasma effluents are formed in a remote region of the semiconductor processing chamber fluidly coupled with, and physically separated from, the processing region of the semiconductor processing chamber.

17. The etching method of claim 16, wherein the water vapor bypasses the remote plasma region of the semiconductor processing chamber when flowed to the processing region of the semiconductor processing chamber.

18. The etching method of claim 14, wherein the fluorine-containing plasma effluents are produced by a capacitively-coupled plasma at a power level of less than or about 500 W.

19. The etching method of claim 14, wherein the first material comprises a spacer material including an oxide material, the second material comprises a hardmask material including a nitride material.

20. The etching method of claim 14, wherein the etching method has a selectivity of at least 5:

1 of the modified first material relative to the modified second material.