PLASMA ACTIVATED CONFORMAL FILM DEPOSITION

• US 20110256726A1
• Filed: 04/11/2011
• Published: 10/20/2011
• Est. Priority Date: 04/15/2010
• Status: Active Grant

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Inventors: van Schravendijk, Bart J., Swaminathan, Shankar, Schlief, Bryan, LaVoie, Adrien, Mountsier, Thomas W., Chandrasekharan, Ramesh, Kang, Hu, Xavier, Antonio, Hausmann, Dennis M., Dorsh, Tom, Jewell, Thomas, Henri, Jon, Li, Ming, Srinivasan, Easwar, Sriram, Mandyam
• Granted Patent: US 8,728,956 B2
• Time in Patent Office: Days
• US Class Current: 438/702
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/4554 Plasma being used non-continuously in between ALD reactions C23C16/56 takes precedence
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/67017 Apparatus for fluid treatment H01L21/67126, H01L21/6715 take precedence
• CPC Class Codes: H01L 21/6719 characterized by the construction of the processing chambers, e.g. modular processing chambers
• CPC Class Codes: H01L 21/67201 characterized by the construction of the load-lock chamber
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264
• CPC Class Codes: H01L 21/76825 by exposing the layer to particle radiation, e.g. ion implantation, irradiation with UV light or electrons etc. plasma treatment H01L21/76826
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76837 Filling up the space between adjacent conductive structures; Gap-filling properties of dielectrics
• CPC Class Codes: H01L 21/76898 : formed through a semiconductor substrate

Abstract

Methods of depositing a film on a substrate surface include surface mediated reactions in which a film is grown over one or more cycles of reactant adsorption and reaction. In one aspect, the method is characterized by the following operations: (a) exposing the substrate surface to a first reactant in vapor phase under conditions allowing the first reactant to adsorb onto the substrate surface; (b) exposing the substrate surface to a second reactant in vapor phase while the first reactant is adsorbed on the substrate surface; and (c) exposing the substrate surface to plasma to drive a reaction between the first and second reactants adsorbed on the substrate surface to form the film.

Claims

1. A method of depositing a film on a substrate surface, the method comprising:

(a) providing a substrate in a reaction chamber;

(b) introducing a first reactant in vapor phase into the reaction chamber under conditions allowing the first reactant to adsorb onto the substrate surface;

(c) introducing a second reactant in vapor phase into the reaction chamber while the first reactant is adsorbed on the substrate surface, wherein the second reactant is introduced without first sweeping the first reactant out of the reaction chamber; and

(d) exposing the substrate surface to plasma to drive a reaction between the first and second reactants on the substrate surface to form the film.

2. The method of claim 1, wherein a plasma is ignited while at least one of the reactants is in a gas phase while being exposed to the substrate.

3. The method of claim 1, wherein the first reactant is an auxiliary reactant.

4. The method of claim 1, wherein the first and second reactants do not react with one another in the vapor phase.

5. The method of claim 1, wherein the amount of said film produced in (d) is limited by the amounts of the first and second reactants adsorbed on the substrate surface.

6. The method of claim 1, wherein the second reactant flows to the substrate surface at a non-constant flow rate during (c).

7. The method of claim 1, further comprising a sweep phase to sweep out the second reactant in vapor phase prior to (d).

8. The method of claim 7, further comprising again exposing the substrate surface to the second reactant after the sweep phase but prior to (d).

10. The method of claim 1, wherein in the film is a dielectric film.

11. The method of claim 1, wherein the first and second reactants co-exist in vapor phase, and wherein the first and second reactants do not appreciably react with one another until exposure to plasma in (d).

12. The method of claim 1, wherein the film formed in (d) forms a conformal structure selected from the group consisting of shallow trench isolation, a through silicon via liner, an interlayer dielectric, a gate spacer, and an intermetal dielectric.

13. The method of claim 1, wherein the film formed in (d) forms an anti-reflective layer.

14. The method of claim 1, wherein the film formed in (d) is a low-k dielectric layer.

15. The method of claim 1, further comprising, after (d), depositing additional film directly on the portion of the film by chemical vapor deposition.

16. The method of claim 1, further comprising:

(e) etching the film at an entrance of the recessed feature; and

(f) depositing an additional portion of the film on the etched film.

17. The method of claim 16, wherein (f) comprises repeating (b)-(d).

18. The method of claim 16, wherein (e) comprises selectively etching the film at the entrance of the recessed feature.

19. The method of claim 1, further comprising:

(e) repeating (b)-(d) at least once;

(f) introducing a third reactant, not introduced during (b)-(e), into the reaction chamber under conditions allowing the third reactant to adsorb onto the substrate surface;

(g) reacting the third reactant to produce a dopant for the film; and

(h) repeating (b)-(d).

47. The method of claim 1 further comprising:

applying photoresist to the substrate;

exposing the photoresist to light;

patterning the resist and transferring the pattern to the substrate; and

selectively removing the photoresist from the substrate.

9. The method of 1, further comprising, prior to (d) introducing a third reactant into the reaction chamber under conditions allowing the third reactant to adsorb onto the substrate surface, and wherein the plasma in (d) drives a reaction between the first, second, and third reactants.

20. A method of depositing a film on a substrate surface, the method comprising:

(a) exposing the substrate surface to a first reactant in vapor phase under conditions allowing the first reactant to adsorb onto the substrate surface;

(b) exposing the substrate surface to a second reactant in vapor phase while the first reactant is adsorbed on the substrate surface; and

(c) exposing the substrate surface to plasma to drive a reaction between the first and second reactants adsorbed on the substrate surface to form the film, wherein the first reactant flows continuously to the substrate and the second reactant flows intermittently to the substrate.

21. The method of claim 20, wherein the first reactant flows to the substrate surface during (b) but the second reactant does not flow to the substrate surface during (a).

22. The method of claim 20, wherein the first reactant does not contain a metal or semiconductor element.

23. The method of claim 20, wherein the first reactant flows continuously but at a non-constant rate.

24. The method of claim 20, wherein the first reactant flows at a reduced flow rate during the intermittent delivery of the second reactant.

25. The method of claim 20, wherein a plasma is ignited while at least one of the reactants is in a gas phase while being exposed to the substrate.

26. A method of depositing a film on a substrate surface, the method comprising:

(a) providing a substrate in a reaction chamber;

(b) introducing a first reactant in vapor phase into the reaction chamber under conditions allowing the first reactant to adsorb onto the substrate surface;

(c) introducing a second reactant in vapor phase into the reaction chamber while the first reactant is adsorbed on the substrate surface;

(d) exposing the substrate surface to plasma to drive a reaction between the first and second reactants on the substrate surface to form the film; and

(e) after the reaction between the first and second reactants to form the film, plasma treating the film to modify at least one property of the film.

27. The method of claim 26, wherein the plasma treating is conducted under plasma conditions that are different from the plasma conditions employed to drive the reaction between the first and second reactants on the substrate surface.

28. The method of claim 26, further comprising repeating (b)-(d) at least once prior performing (e).

29. The method of claim 26, wherein the property of the deposited film modified by the plasma treating in (e) is selected from the group consisting of internal film stress, etch resistance, density, hardness, an optical property, dielectric constant, carbon content, and an electrical property.

30. The method of claim 26, wherein treating the deposited film (e) changes the composition of the film.

31. The method of claim 26, wherein treating the deposited film (e) removes a contaminant from the film.

32. The method of claim 26, further comprising sweeping the reaction chamber after (d) and before (e).

33. An apparatus for depositing films on a substrate, the apparatus comprising:

a reaction chamber;

an inlet port for delivering gas phase reactants to the reaction chamber;

a plasma generator for providing plasma to the reaction chamber; and

a controller comprising instructions for

(a) flowing a first reactant in vapor phase into the reaction chamber under conditions allowing the first reactant to adsorb onto a substrate surface;

(b) flowing a second reactant in vapor phase into the reaction chamber while the first reactant is adsorbed on the substrate surface, such that the first reactant flows continuously to the substrate and the second reactant flows intermittently to the substrate; and

(c) providing a plasma in the reaction chamber to drive a reaction between the first and second reactants adsorbed on the substrate surface to form a film.

34. An apparatus for depositing films on a substrate, the apparatus comprising:

a reaction chamber;

an inlet port for delivering gas phase reactants to the reaction chamber;

a plasma generator for providing plasma to the reaction chamber; and

a controller comprising instructions for

(a) introducing a first reactant in vapor phase into the reaction chamber under conditions allowing the first reactant to adsorb onto a substrate surface held in the reaction chamber;

(b) introducing a second reactant in vapor phase into the reaction chamber while the first reactant is adsorbed on the substrate surface, wherein the second reactant is introduced without first sweeping the first reactant out of the reaction chamber; and

(c) exposing the substrate surface to plasma to drive a reaction between the first and second reactants on the substrate surface to form a film.

35. The apparatus of claim 34, wherein the controller further comprises instructions for performing chemical vapor deposition to deposit additional film on the substrate surface.

36. The apparatus of claim 34, wherein the controller further comprises instructions for

(d) etching the film;

and

(e) depositing additional film on the etched film.

37. The apparatus of claim 34, wherein the controller further comprises instructions for monitoring the plasma provided by instruction (c) using an optical emission spectroscopy sensor or a current voltage probe.

38. The apparatus of claim 34, further comprising a mixing bowl connected to the inlet port, wherein the mixing bowl is configured to mix two more process gases prior to delivery to the reaction chamber via the inlet port.

39. The apparatus of claim 34, wherein the reaction chamber comprises a plurality of stations each with its own substrate holder.

40. The apparatus of claim 34, wherein the instructions for providing a plasma in the reaction chamber comprise instructions for allowing the frequency of the plasma generator to float.

41. The apparatus of claim 34, wherein the controller further comprises looping instructions for repeatedly performing cycles of flowing of the first and second reactants and the providing a plasma to drive the reaction between the first and second reactants adsorbed on the substrate surface.

42. A system comprising the apparatus of claim 34 and a stepper.

43. An apparatus for depositing films on a substrate, the apparatus comprising:

a reaction chamber;

an inlet port for delivering gas phase reactants to the reaction chamber;

a plasma generator for providing plasma to the reaction chamber; and

a controller comprising instructions for

(a) introducing a first reactant in vapor phase into the reaction chamber under conditions allowing the first reactant to adsorb onto a substrate surface;

(b) introducing a second reactant in vapor phase into the reaction chamber while the first reactant is adsorbed on the substrate surface;

(c) exposing the substrate surface to plasma to drive a reaction between the first and second reactants on the substrate surface to form a film; and

(d) after the reaction between the first and second reactants to form the film, plasma treating the film to modify at least one property of the film.

44. The apparatus of claim 43, wherein the instructions for plasma treating the deposited film comprises instructions for conducting the plasma treating under conditions that are different from the plasma conditions specified in the instructions for driving reaction between the first and second reactants on the substrate surface.

45. The apparatus of claim 43, wherein the controller further comprises instructions for repeating (a)-(c) at least once prior performing (d).

46. The apparatus of claim 43, wherein the controller further comprises instructions for sweeping the reaction chamber after (c) and before (d).