Deposition of boron and carbon containing materials

• US 9,362,109 B2
• Filed: 10/15/2014
• Issued: 06/07/2016
• 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:
  US14/515,395
• Publication Number:
  US 20150104955A1
• Time in Patent Office: 601 Days
• Field of Search: 438/791
• 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 silicon nitride thin film comprising boron and carbon on a substrate in a reaction space comprising:

at least one silicon nitride cycle comprising;

contacting the substrate with a vapor-phase silicon precursor;

contacting the substrate with a nitrogen reactant; and

subsequently contacting the substrate with a vapor phase boron precursor, to form a SiN_x(B_y,C_z) thin film, wherein x is from 0.5 to 3.0, wherein y is from 0.1 to 5.0, and wherein z is from 0.1 to 5.0.

2. The method of claim 1, wherein the silicon nitride cycle is performed two or more times.

3. The method of claim 2, wherein contacting the substrate with the vapor phase boron precursor is performed after each silicon nitride cycle.

4. The method of claim 2, wherein a number of silicon nitride cycles is performed at a ratio to a number of times of contacting the substrate with the vapor phase boron precursor.

5. The method of claim 4, wherein the ratio is from 1:

1 to 100;

1.

6. The method of claim 1, wherein no plasma reactant is provided.

7. The method of claim 1, wherein contacting the substrate with the nitrogen-containing reactant comprises a plasma process.

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

9. The method of claim 1, wherein the silicon nitride cycle comprises an atomic layer deposition process.

10. The method of claim 9, wherein the vapor phase boron precursor decomposes on the substrate.

11. The method of claim 1, wherein the silicon precursor is selected from the group consisting of silicon halides, silicon alkylamines, and silanes.

12. The method of claim 1, wherein the boron precursor is selected from the group consisting of boron halides, alkylborons, and boranes.

13. The method of claim 1, wherein the boron precursor decomposes on the substrate.

14. The method of claim 1, wherein the silicon nitride thin film is deposited over a three-dimensional structure.

15. The method of claim 1, wherein the silicon nitride thin film has an etch rate of less than 0.2 nm/min in dilute hydrofluoric acid solution.

16. A method of depositing a silicon nitride thin film on a substrate in a reaction space comprising:

a silicon nitride cycle comprising;

contacting the substrate with a vapor-phase silicon precursor so that the silicon precursor is adsorbed to a surface of the substrate;

removing excess silicon precursor and reaction byproducts from the substrate surface;

contacting the adsorbed silicon precursor substrate with a nitrogen reactant; and

subsequently contacting the substrate with a vapor-phase boron precursor, to form a SiN_x(B_y,C_z) thin film, wherein x is from 0.5 to 3.0, wherein y is from 0.1 to 5.0, and wherein z is from 0.1 to 5.0, wherein the vapor-phase boron precursor decomposes on the substrate.

17. The method of claim 16, wherein the silicon nitride cycle is performed two or more times.

18. The method of claim 17, wherein contacting the substrate with the vapor phase boron precursor is performed after each silicon nitride cycle.

19. The method of claim 17, wherein a number of silicon nitride cycles is performed at a ratio to a number of times of contacting the substrate with the vapor phase boron precursor.

20. The method of claim 19, wherein the ratio is from 1:

1 to 100;

1.

21. The method of claim 16, wherein a process temperature of the method is 200°

C. to 400°

C.

22. The method of claim 16, wherein the silicon nitride thin film has a boron content of 0.1 to 50 atomic %.

23. The method of claim 16, wherein the silicon nitride thin film has a carbon content of 0.1 to 50 atomic %.

24. The method of claim 16, wherein a boron atom in the silicon nitride thin film is bonded to a carbon atom.

25. The method of claim 16, further comprising treating the silicon nitride thin film in an oxygen-containing atmosphere and etching the treated silicon nitride thin film.

26. The method of claim 16, wherein the silicon nitride thin film is deposited conformally over a three-dimensional structure having an aspect ratio of greater than 8:

1.

27. The method of claim 26, wherein the silicon nitride thin film has a step coverage of greater than 95%.

28. The method of claim 26, wherein a ratio of an etch rate of the silicon nitride thin film in a sidewall of the three-dimensional structure to an etch rate of the silicon nitride thin film on a top surface of the three-dimensional structure is less than 4.

29. The method of claim 16, wherein the silicon nitride thin film has a wet etch rate ratio to thermal silicon oxide of less than 0.5 in dilute hydrofluoric acid solution.

30. The method of claim 16, wherein the silicon nitride thin film comprising boron and carbon is substantially free of distinct layers.