Tensile nitride deposition systems and methods

Patent metadata

Field	Value
Publication number	US-11710631-B2
Application number	US-202017078793-A
Country	US
Kind code	B2
Filing date	Oct 23, 2020
Priority date	Oct 23, 2020
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

Exemplary semiconductor processing methods may include flowing deposition gases that may include a nitrogen-containing precursor, a silicon-containing precursor, and a carrier gas, into a substrate processing region of a substrate processing chamber. The flow rate ratio of the nitrogen-containing precursor to the silicon-containing precursor may be greater than or about 1:1. The methods may further include generating a deposition plasma from the deposition gases to form a silicon-and-nitrogen containing layer on a substrate in the substrate processing chamber. The silicon-and-nitrogen-containing layer may be treated with a treatment plasma, where the treatment plasma is formed from the carrier gas without the silicon-containing precursor. The flow rate of the carrier gas in the treatment plasma may be greater than a flow rate of the carrier gas in the deposition plasma.

First claim

The invention claimed is:

1. A semiconductor processing method comprising:
flowing deposition gases comprising a nitrogen-containing precursor, a silicon-containing precursor, and a carrier gas, into a substrate processing region of a substrate processing chamber, wherein a flow rate ratio of the nitrogen-containing precursor to the silicon-containing precursor is greater than or about 1:1;
generating a deposition plasma from the deposition gases to form a silicon-and-nitrogen-containing layer on a substrate in the substrate processing chamber; and
treating the silicon-and-nitrogen-containing layer with a treatment plasma, wherein the treatment plasma increases a tensile stress of the treated portion of the silicon-and-nitrogen-containing layer, wherein the treatment plasma is formed from the carrier gas without the silicon-containing precursor, and wherein a flow rate of the carrier gas in the treatment plasma is greater than a flow rate of the carrier gas in the deposition plasma.

2. The semiconductor processing method of claim 1 , wherein the nitrogen-containing precursor comprises ammonia, and wherein the ammonia has a flow rate greater than or about 100 sccm.

3. The semiconductor processing method of claim 1 , wherein the silicon containing precursor comprises silane, and wherein the silane has a flow rate greater than or about 50 sccm.

4. The semiconductor processing method of claim 1 , carrier gas comprises molecular nitrogen (N 2 ) and argon, wherein the molecular nitrogen has a flow rate greater than or about 5000 sccm, and the argon has a flow rate greater than or about 2000 sccm.

5. The semiconductor processing method of claim 1 , wherein the silicon-and-nitrogen-containing layer is formed at a deposition rate less than or about 10 Å/second.

6. The semiconductor processing method of claim 1 , wherein the generation of the deposition plasma further comprises delivering to the deposition gases a plasma power less than or about 60 Watts.

7. The semiconductor processing method of claim 1 , wherein the substrate processing chamber is characterized by a deposition chamber pressure during the deposition of the silicon-and-nitrogen-containing layer that is less than the treatment chamber pressure during the treating of the silicon-and-nitrogen-containing layer.

8. The semiconductor processing method of claim 1 , wherein a post-treatment silicon-and-nitrogen-containing layer comprises a silicon nitride layer characterized by a tensile stress greater than or about 1 GPa, and a wet etch rate less than or about 20 Å/minute.

9. A semiconductor processing method comprising:
depositing a silicon-and-nitrogen-containing layer on a substrate in a substrate processing region of a substrate processing chamber, wherein the silicon-and-nitrogen-containing layer is deposited with a deposition plasma generated from a deposition gas comprising a nitrogen-containing precursor and a silicon-containing precursor, and wherein the deposition plasma is formed with a first plasma power; and
treating the silicon-and-nitrogen-containing layer with a treatment plasma, wherein the treatment plasma increases a tensile stress of the treated portion of the silicon-and-nitrogen-containing layer, wherein the treatment plasma is formed with a second plasma power that is greater than the first plasma power, and wherein the silicon-and-nitrogen-containing layer is characterized by a tensile stress greater than or about 1 GPa, and a wet etch rate less than or about 20 Å/minute.

10. The semiconductor processing method of claim 9 , wherein the first plasma power is less than or about 60 Watts and the second plasma power is greater than or about 100 Watts.

11. The semiconductor processing method of claim 9 , wherein the silicon-and-nitrogen-containing layer comprises a silicon nitride layer with a hydrogen level less than or about 3 at. %.

12. The semiconductor processing method of claim 9 , wherein the treatment plasma is formed from a treatment gas without the silicon-containing precursor or the nitrogen-containing precursor.

13. The semiconductor processing method of claim 9 , wherein the treatment plasma is formed from a treatment gas comprising molecular nitrogen (N 2 ), and wherein the molecular nitrogen is delivered to the substrate processing chamber at a nitrogen flow rate greater than or about 10,000 sccm.

14. The semiconductor processing method of claim 9 , wherein the silicon-and-nitrogen-containing layer is formed at a deposition rate less than or about 10 Å/second.

15. A semiconductor processing method comprising:
forming a silicon nitride layer, wherein the silicon nitride layer is formed by two or more cycles that comprise:
depositing a portion of a silicon nitride layer on a substrate in a substrate processing region of a substrate processing chamber, wherein the portion of the silicon nitride layer is deposited to a thickness less than or about 15 Å, and
treating the portion of the silicon nitride layer with a treatment plasma, wherein the treatment plasma increases a tensile stress and wet etch rate of the treated portion of the silicon nitride layer compared to the as-deposited portion, and wherein the treated portion of the silicon nitride layer is characterized by a hydrogen level less than or about 3 at. %.

16. The semiconductor processing method of claim 15 , wherein the entire silicon nitride layer has a thickness greater than or about 300 Å.

17. The semiconductor processing method of claim 15 , wherein the portion of the silicon nitride layer is treated with the treatment plasma for less than or about 15 seconds.

18. The semiconductor processing method of claim 15 , wherein the portion of the silicon nitride layer is deposited from a deposition plasma that is generated from deposition gases delivered to the substrate processing chamber, and wherein the deposition gases comprise a nitrogen-containing precursor, a silicon-containing precursor, and further wherein the nitrogen containing precursor has a flow rate less than or about 200 sccm, and the silicon-containing precursor has a flow rate less than 100 sccm.

19. The semiconductor processing method of claim 15 , wherein the portion of the silicon nitride layer is formed at a deposition rate less than or about 10 Å/second.

20. The semiconductor processing method of claim 15 , wherein the entire silicon nitride layer is characterized by a tensile stress greater than or about 1 GPa, and a wet etch rate less than or about 20 Å/minute.

Assignees

• Applied Materials Inc

Inventors

• Tsiang Michael Wenyoung
• Lin Yichuen
• Hsiao Kevin
• Yu Hang
• Padhi Deenesh
• Liu Yijun
• Xia Li-Qun

Classifications

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/6682

  the compound being a silane, e.g. disilane, methylsilane or chlorosilane · CPC title

• H10P14/6336 Primary

  in the presence of a plasma [PECVD] · CPC title

• H10P14/6532 Primary

  by exposure to a plasma · CPC title

• H10P72/72

  using electrostatic chucks · CPC title