Deposition of boron and carbon containing materials

• US 9,543,140 B2
• Filed: 10/15/2014
• Issued: 01/10/2017
• Est. Priority Date: 10/16/2013
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Pore, Viljami
• Primary Examiner(s): Sarkar, Asok K
• Application Number:
  US14/515,341
• Publication Number:
  US 20150104954A1
• Time in Patent Office: 818 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/30 Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
• CPC Class Codes: C23C 16/32 Carbides
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: H01L 21/02112 characterised by the material of the layer
• 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 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/31111 by chemical means

Abstract

Methods of depositing boron and carbon containing films are provided. In some embodiments, methods of depositing B,C films with desirable properties, such as conformality and etch rate, are provided. One or more boron and/or carbon containing precursors can be decomposed on a substrate at a temperature of less than about 400° C. In some embodiments methods of depositing silicon nitride films comprising B and C are provided. A silicon nitride film can be deposited by a deposition process including an ALD cycle that forms SiN and a CVD cycle that contributes B and C to the growing film.

Claims

1. A method of depositing a B_xC film on a substrate in a reaction space, comprising:

contacting the substrate with a vapor phase boron precursor at a process temperature of less than 400°

C. to form the B_xC film on the substrate, wherein x is 0.1 to 25, wherein the vapor phase boron precursor decomposes on the substrate, and wherein the B_xC film has an etch rate in dilute hydrofluoric acid solution of less than 0.2 nm/min.

2. The method of claim 1, further comprising contacting the substrate with a carrier gas comprising nitrogen.

3. The method of claim 1, further comprising contacting the substrate with a carrier gas comprising at least one of helium and neon.

4. The method of claim 1, wherein the B_xC film has an etch rate in dilute hydrofluoric acid solution of less than 0.02 nm/min.

5. The method of claim 1, wherein a film density of the B_xC film is less than 2.5 g/cm³.

6. The method of claim 1, wherein the substrate comprises silicon.

7. The method of claim 6, wherein the substrate comprises silicon nitride.

8. The method of claim 1, wherein the substrate comprises a three-dimensional structure, and wherein contacting the substrate with the reactant pulse comprises contacting the reactant pulse with the three-dimensional structure on the substrate to form the B_xC film on the three-dimensional structure.

9. The method of claim 8, wherein the B_xC film has a step cover of greater than 95%.

10. The method of claim 1, further comprising maintaining a pressure of 0.5 Torr to 3 Torr within the reaction space during contacting the substrate with the vapor phase boron precursor.

11. The method of claim 1, wherein the reaction space is part of a batch reactor.

12. The method of claim 1, further comprising exposing the B_xC film to a post-deposition plasma treatment process subsequent to depositing the B_xC film.

13. The method of claim 12, wherein the post-deposition plasma treatment process comprises generating a plasma from at least one of a noble gas, nitrogen gas, oxygen gas, and ozone.

14. A method of forming a B_xC film on a substrate in a reaction space, comprising:

contacting a three-dimensional structure on the substrate with a vapor phase boron precursor at a process temperature of less than 400°

C. to form the B_xC film on the three-dimensional structure, wherein x is 0.1 to 25, wherein the B_xC film has a step coverage of greater than 80%, and wherein the B_xC film has a wet etch rate in dilute hydrofluoric acid solution of less than 0.2 nm/min; and

purging the reaction space subsequent to contacting the three-dimensional structure on the substrate with the vapor phase boron precursor.

15. The method of claim 14, wherein the three-dimensional structure has an aspect ratio of greater than 8:

1.

16. The method of claim 14, wherein the B_xC film has a wet etch rate ratio relative to that of thermal silicon oxide of less than 0.3.

17. The method of claim 14, wherein the B_xC film has a film density of 2.0 g/cm³ to 2.5 g/cm³.

18. The method of claim 14, wherein the process temperature is between 375°

C. and 400°

C.

19. The method of claim 14, wherein the process temperature is less than 350°

C.

20. The method of claim 14, further comprising exposing the B_xC to a post-deposition plasma treatment process subsequent to depositing the B_xC.