CN-122029303-A - Seamless gap filling by suppressed atomic layer deposition

Abstract

Examples are disclosed relating to filling gaps in a substrate using suppressed Plasma Enhanced Atomic Layer Deposition (PEALD) involving sputtering. An example provides a method comprising performing a plurality of PEALD cycles. The PEALD cycle includes, in the suppressing step, forming a plasma using a gas mixture including an inhibitor to deposit the inhibitor into the gap on the substrate such that a concentration of the inhibitor deposited at a first depth is greater than a concentration of the inhibitor deposited deeper within the gap. The PEALD cycle further includes, during the depositing step, adsorbing the silicon-containing film precursor to the substrate, and forming a plasma to convert the silicon-containing film precursor within the gap to a silicon-containing film. At least one of the inhibiting step or the depositing step includes exposing the substrate to a plasma under conditions configured to sputter the silicon-containing film.

Inventors

• Jason Alexander Vanell
• Jonathan Grant Baker
• Porket Agarwal
• GUI ZHE
• Jennifer Lee petralia

Assignees

• 朗姆研究公司

Dates

Publication Date

20260512

Application Date

20240819

Priority Date

20230821

Claims (20)

1. 1. A method of processing a substrate including a gap, the method comprising: Performing a plurality of Plasma Enhanced Atomic Layer Deposition (PEALD) cycles to deposit a silicon-containing film into the gap, a PEALD cycle of the plurality of PEALD cycles comprising In the suppressing step, forming a plasma using a gas mixture comprising an inhibitor to expose the substrate to the inhibitor under conditions configured to deposit the inhibitor into the gap such that a concentration of the inhibitor deposited at a first depth within the gap is greater than a concentration of the inhibitor deposited at a second depth within the gap, the second depth being deeper in the gap than the first depth, and In the course of the deposition step, Adsorbing a silicon-containing film precursor to the substrate, the inhibitor causing a concentration of the silicon-containing film precursor adsorbed at the first depth to be less than at the second depth, and Forming a plasma to convert the silicon-containing film precursor adsorbed to the substrate within the gap into a silicon-containing film, Wherein at least one of the inhibiting step or the depositing step comprises exposing the substrate to a plasma under conditions configured to sputter the silicon-containing film.
2. 2. The method of claim 1, wherein the plasma conditions are configured to sputter a portion of the silicon-containing film material from the first depth within the gap and redeposit at least some of the portion of the silicon-containing film material at the second depth within the gap.
3. 3. The method of claim 1, wherein the suppressing step is performed at a first pressure of 5 torr or less and the depositing step is performed at a second pressure equal to or greater than the first pressure.
4. 4. The method of claim 1, wherein the depositing step is performed at a first pressure of 2 torr or less and the suppressing step is performed at a second pressure of 5 torr or greater.
5. 5. The method of claim 1, wherein the plasma conditions configured to sputter the silicon-containing film comprise a plasma formed using a radio frequency power of 1000W to 6000W.
6. 6. The method of claim 1, wherein the method comprises heating the substrate to a temperature of 50 ℃ to 650 ℃.
7. 7. The method of claim 1, wherein the substrate comprises a first fin and a second fin, the gap is provided between the first fin and the second fin, and after the silicon-containing film is deposited into the gap, the first fin and the second fin are each off vertical by less than 0.5nm measured on top of the first fin and on top of the second fin.
8. 8. The method of claim 1, wherein the substrate comprises silicon and germanium, and the depositing step is performed under conditions configured to avoid oxidation of the germanium.
9. 9. The method of claim 1, wherein the silicon-containing film comprises one of silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbide, silicon carbonitride, or silicon oxycarbonitride.
10. 10. The method of claim 1, wherein the inhibitor comprises one or more of nitrogen, hydrogen, ammonia, or nitrogen trifluoride.
11. 11. The method of claim 1, wherein forming the plasma to convert the silicon-containing film precursor to a silicon-containing film comprises forming a plasma using an oxidizing agent comprising one or more of nitrous oxide or carbon dioxide at a concentration greater than an oxygen concentration.
12. 12. The method of claim 1, wherein at least one PEALD cycle of the plurality of PEALD cycles omits the inhibiting step.
13. 13. An Atomic Layer Deposition (ALD) tool, comprising: A processing chamber; a substrate support disposed in the process chamber; Flow control hardware configured to control gas flow from an inhibitor source, a silicon-containing film precursor source, and an inert gas source into the process chamber; A radio frequency power source configured to form a plasma in the process chamber, and A controller configured to control the ALD tool to In the suppressing step, operating the flow control hardware to flow the suppressor into the process chamber, and Operating the radio frequency power source to form a plasma under conditions configured to deposit an inhibitor within a gap on a substrate such that a concentration of the inhibitor deposited at a first depth within the gap is greater than a concentration of the inhibitor deposited at a second depth within the gap, the second depth being deeper in the gap than the first depth; in the course of the deposition step, Operating the flow control hardware to flow the silicon-containing film precursor to the process chamber to adsorb the silicon-containing film precursor onto the substrate, and Operating the RF power source to form a plasma to oxidize the film precursor to form an oxidized film layer, and In one or more of the suppressing step or the depositing step, the flow control hardware and the radio frequency power source are operated to form a plasma using one or more of the suppressor, oxidizer, nitrogen, or inert gas under conditions configured to sputter the silicon-containing film.
14. 14. The ALD tool of claim 13, wherein the controller is configured to operate the flow control hardware in the suppressing step to create a first pressure of 5 torr or less in the process chamber and to operate the flow control hardware in the depositing step to create a second pressure in the process chamber that is equal to or greater than the first pressure.
15. 15. The ALD tool of claim 13, wherein the controller is configured to operate the flow control hardware to create a first pressure of 5 torr or greater in the process chamber during the suppressing step and to operate the flow control hardware to create a second pressure of 2 torr or less in the process chamber during the depositing step.
16. 16. The ALD tool of claim 13, further comprising the inhibitor source comprising the inhibitor, the inhibitor comprising one or more of nitrogen, hydrogen, ammonia, or nitrogen trifluoride.
17. 17. A method of processing a substrate including a gap, the method comprising: Heating the substrate to a temperature of 650 ℃ or less; Performing a plurality of Plasma Enhanced Atomic Layer Deposition (PEALD) cycles while heating the substrate to deposit a silicon-containing film into the gap, PEALD cycles of the plurality of PEALD cycles comprising In the suppressing step, forming a plasma using a gas mixture comprising an inhibitor to expose the substrate to the inhibitor under conditions configured to deposit inhibitor into the gap such that a concentration of the inhibitor deposited at a first depth within the gap is greater than a concentration of the inhibitor deposited at a second depth within the gap, the second depth being deeper in the gap than the first depth, and In the course of the deposition step, Exposing the substrate to a silicon-containing film precursor to adsorb the silicon-containing film precursor on the substrate, the inhibitor causing the concentration of the silicon-containing film precursor adsorbed at the first depth to be less than at the second depth, and Forming a plasma to convert the silicon-containing film precursor within the gap to a silicon-containing film, Wherein at least one of the inhibiting step or the depositing step comprises exposing the substrate to a plasma comprising one or more of the inhibitor, oxidant, nitrogen, or inert gas while the silicon-containing film is grown under plasma conditions configured to sputter the silicon-containing film to avoid formation of seams in the silicon-containing film within the gap.
18. 18. The method of claim 17, wherein the suppressing step is performed at a first pressure of 5 torr or less and the depositing step is performed at a second pressure equal to or greater than the first pressure.
19. 19. The method of claim 17, wherein the depositing step is performed at a first pressure of 2 torr or less and the suppressing step is performed at a second pressure of 5 torr or greater.
20. 20. The method of claim 17, wherein the substrate comprises a first fin and a second fin, the gap is provided between the first fin and the second fin, and after the silicon-containing film is deposited into the gap, the first fin and the second fin are each off vertical by less than 0.5nm measured on top of the first fin and on top of the second fin.

Description

Seamless gap filling by suppressed atomic layer deposition Background Electronic device manufacturing processes involve numerous steps of material deposition, patterning, and removal to form integrated circuits on a substrate. The film of material may be processed using a variety of methods to form integrated circuits. For example, atomic Layer Deposition (ALD) may be utilized to form films on substrates in a layer-by-layer fashion. ALD can be used to form highly conformal films on complex substrate topologies. Disclosure of Invention This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure. Examples are disclosed regarding filling recessed structures ("gaps") in a substrate using suppressed Plasma Enhanced Atomic Layer Deposition (PEALD) including sputtering. An example provides a method of processing a substrate including a gap. The method includes performing a plurality of PEALD cycles to deposit a silicon-containing film into the gap. The PEALD cycles of the plurality of PEALD cycles include forming, in a step of suppressing, a plasma using a gas mixture including an inhibitor to expose the substrate to the inhibitor under conditions configured to deposit inhibitor into the gap such that a concentration of the inhibitor deposited at a first depth within the gap is greater than a concentration of the inhibitor deposited at a second depth within the gap, the second depth being deeper in the gap than the first depth. The PEALD cycles of the plurality of PEALD cycles further comprise adsorbing a silicon-containing film precursor to the substrate during the depositing step, the inhibitor resulting in a concentration of the silicon-containing film precursor adsorbed at the first depth that is less than at the second depth. The PEALD cycle of the plurality of PEALD cycles further includes forming a plasma to convert the silicon-containing film precursor adsorbed to the substrate within the gap into a silicon-containing film during the depositing step. At least one of the inhibiting step or the depositing step includes exposing the substrate to a plasma under conditions configured to sputter the silicon-containing film. In some such examples, the plasma conditions are configured to sputter a portion of the silicon-containing film material from the first depth within the gap and redeposit at least some of the portion of the silicon-containing film material at the second depth within the gap. In some such examples, the suppressing step is additionally or alternatively performed at a first pressure of 5 torr or less, and the depositing step is performed at a second pressure equal to or greater than the first pressure. In some such examples, the suppressing step is additionally or alternatively performed at a first pressure of 2 torr or less, and the suppressing step is performed at a second pressure of 5 torr or greater. In some such examples, the plasma conditions configured to sputter the silicon-containing film additionally or alternatively include a plasma formed using a radio frequency power of 1000W to 6000W. In some such examples, the method additionally or alternatively includes heating the substrate to a temperature of 50 ℃ to 650 ℃. In some such examples, the substrate additionally or alternatively includes a first fin and a second fin, the gap is provided between the first fin and the second fin, and after the silicon-containing film is deposited into the gap, the first fin and the second fin are each offset from vertical by less than 0.5nm measured on top of the first fin and on top of the second fin. In some such examples, the substrate additionally or alternatively comprises silicon and germanium, and the depositing step is performed under conditions configured to avoid oxidation of the germanium. In some such examples, the silicon-containing film additionally or alternatively includes one of silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbide, silicon carbonitride, or silicon oxycarbonitride. In some such examples, the inhibitor additionally or alternatively comprises one or more of nitrogen, hydrogen, ammonia, or nitrogen trifluoride. In some such examples, forming the plasma to convert the silicon-containing film precursor to the silicon-containing film additionally or alternatively includes forming the plasma using an oxidizing agent comprising one or more of nitrous oxide or carbon dioxide at a concentration greater than an oxygen concentration. In some such examples, at least one PEALD cycle of the plurality of PEALD cycles additionally or alter