Apparatus And Methods For Deposition Of Silicon Carbide And Silicon Carbonitride Films

• US 20120122302A1
• Filed: 11/03/2011
• Published: 05/17/2012
• Est. Priority Date: 11/03/2010
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Weidman, Timothy W., Schroeder, Todd
• Granted Patent: US 8,440,571 B2
• Time in Patent Office: Days
• US Class Current: 438/478
• CPC Class Codes: C23C 16/325 Silicon carbide
• CPC Class Codes: C23C 16/36 Carbonitrides
• CPC Class Codes: C23C 16/4554 Plasma being used non-continuously in between ALD reactions C23C16/56 takes precedence
• CPC Class Codes: C23C 16/5096 Flat-bed apparatus
• CPC Class Codes: H01L 21/02167 the material being a silicon carbide not containing oxygen, e.g. SiC, SiC:H or silicon carbonitrides 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 21/02329 introduction of nitrogen
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/02447 Silicon carbide
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD

Abstract

Methods for deposition of silicon carbide films on a substrate surface are provided. The methods include the use of vapor phase carbosilane precursors and may employ plasma enhanced atomic layer deposition processes. The methods may be carried out at temperatures less than 600° C., for example between about 23° C. and about 200° C. or at about 100° C. This silicon carbide layer may then be densified to remove hydrogen content. Additionally, the silicon carbide layer may be exposed to a nitrogen source to provide reactive N—H groups, which can then be used to continue film deposition using other methods. Plasma processing conditions can be used to adjust the carbon, hydrogen and/or nitrogen content of the films.

Claims

1. A method for forming a silicon carbide film on a substrate surface comprising exposing a substrate having a reactive surface to a vapor phase carbosilane precursor to form a silicon carbide layer on the substrate surface, wherein the carbosilane precursor contains at least one carbon atom bridging at least two silicon atoms.

2. The method of claim 1, further comprising treating the silicon carbide layer with a plasma effective to remove hydrogen.

3. The method of claim 1 wherein the carbosilane precursor is 1,3-disilapropane, 1,3-disilabutane, 1,3-disilacyclobutane, 1,3,5-trisilacyclohexane, 1,3,5-tisilahexane, 1,3,5-trisilapentane, 1,3,5,7-tetrasilaheptane, and 2,4,6-trisilaheptane.

4. The method of claim 1, wherein the reactive surface is produced by plasma treatment of the substrate.

5. The method of claim 1, wherein the substrate is exposed to the vapor phase carbosilane precursor at a temperature of less than 600°

C.

6. The method of claim 5, wherein the substrate is exposed to the vapor phase carbosilane precursor at a temperature between about 23°

C. and about 200°

C.

7. The method of claim 1, further comprising treating the silicon carbide layer on the substrate surface with a plasma to activate the silicon carbide layer and exposing the activated silicon carbide layer to a second vapor phase carbosilane precursor to form an additional silicon carbide layer on the substrate surface.

8. The method of claim 7, wherein the second vapor phase silicon carbide is different from the silicon carbide in the activated silicon carbide layer.

9. A method of forming a layer on a substrate surface, the method comprising:

exposing the substrate surface to a carbosilane precursor containing at least one carbon atom bridging at least two silicon atoms;

exposing the carbosilane precursor to a low-power energy source to provide a carbosilane at the substrate surface;

densifying the carbosilane; and

exposing the carbosilane surface to a nitrogen source.

10. The method of claim 9, wherein densifying the carbosilane comprises exposing the substrate surface to a plasma containing one or more of He, Ar and H₂.

11. The method of claim 9, wherein the carbosilane precursor contains a methylene group bridging at least two silicon atoms.

12. The method of claim 11, wherein the carbosilane precursor is one or more of 1,3-disilapropane, 1,3-disilabutane, 1,3-disilacyclobutane, 1,3,5-trisilacyclohexane, 1,3,5-tisilahexane, 1,3,5-trisilapentane, 1,3,5,7-tetrasilaheptane, and 2,4,6-trisilaheptane.

13. The method of claim 9, wherein exposing the carbosilane to a nitrogen source comprises flowing ammonia or exposing the carbosilane to a plasma containing nitrogen.

15. The method of claim 9, wherein exposing the carbosilane precursor to a low-power energy source comprises exposing the carbosilane precursor to a low-power plasma, ultraviolet radiation, electron beam or ion beam.

16. The method of claim 9 wherein the low-power plasma has a value of about 10 W to about 200 W.

17. The method of claim 9, wherein the carbosilane precursor is exposed to the low-power plasma for about 0.10 seconds to about 5.0 seconds.

14. The method of 13, wherein exposing the carbosilane to a plasma containing nitrogen results in the formation of N—

H bonds that promote irreversible attachment of a monolayer of the carbosilane to the substrate surface.

18. An apparatus to form a layer on a substrate by plasma enhanced atomic layer deposition, the apparatus comprising:

a deposition chamber;

a substrate stage in the deposition chamber to hold the substrate;

a plasma generating system coupled to the deposition chamber, wherein the plasma generating system is used to generate a reactive plasma;

a gas distribution system comprising a dual-channel showerhead positioned above the substrate stage, wherein the showerhead comprises a faceplate with a first set of openings through which the plasma species enter the deposition chamber, and a second set of openings through which a precursor enters the deposition chamber, and wherein the plasma species and the precursor are not mixed until entering the deposition chamber.

19. The apparatus of claim 18, wherein the plasma is generated remotely from the deposition chamber.

20. The apparatus of claim 18, wherein the precursor comprises one or more of 1,3-disilapropane, 1,3-disilabutane, 1,3-disilacyclobutane, 1,3,5-trisilacyclohexane, 1,3,5-tisilahexane, 1,3,5-trisilapentane, 1,3,5,7-tetrasilaheptane, and 2,4,6-trisilaheptane.