DIELECTRIC FILM FORMATION USING INERT GAS EXCITATION

• US 20110165347A1
• Filed: 09/02/2010
• Published: 07/07/2011
• Est. Priority Date: 01/05/2010
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Yang, Jang-Gyoo, Miller, Matthew L.
• Granted Patent: US 8,329,262 B2
• Time in Patent Office: Days
• US Class Current: 427/579
• 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 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01J 2237/3327 Coating high aspect ratio workpieces
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• 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 21/02222 the compound being a silazane
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02326 into a nitride layer, e.g. changing SiN to SiON

Abstract

Methods of forming a silicon-and-nitrogen-containing layers and silicon oxide layers are described. The methods include the steps of mixing a carbon-free silicon-containing precursor with plasma effluents, and depositing a silicon-and-nitrogen-containing layer on a substrate. The silicon-and-nitrogen-containing layers may be made flowable or conformal by selection of the flow rate of excited effluents from a remote plasma region into the substrate processing region. The plasma effluents are formed in a plasma by flowing inert gas(es) into the plasma. The silicon-and-nitrogen-containing layer may be converted to a silicon-and-oxygen-containing layer by curing and annealing the film.

Claims

1. A method of forming a silicon-and-nitrogen-containing layer on a substrate in a substrate processing region in a substrate processing chamber, the method comprising:

flowing gas into a plasma region to produce excited effluents, wherein the combination of all gases in the plasma region during deposition consist essentially of inert gases which do not form chemical bonds within the silicon-and-nitrogen-containing layer;

combining a carbon-free silicon-containing precursor with the plasma effluents in the substrate processing region, wherein the excited effluents cause a reaction in the carbon-free silicon-containing precursor; and

depositing a silicon-and-nitrogen-containing layer on the substrate.

2. The method of claim 1 wherein the combination of all gases consist of inert gases.

3. The method of claim 1 wherein the substrate processing region is plasma-free in that plasma power is not applied to the substrate processing region in order to avoid direct plasma excitation of the carbon-free silicon-containing precursor.

4. The method of claim 1 wherein excited effluents are delivered at a relatively low flow rate into the substrate processing region is maintained whereby the silicon-and-nitrogen-containing layer is made flowable during deposition.

5. The method of claim 4 wherein the relatively low flow of excited effluents into the substrate processing region is ensured by maintaining a reduced plasma power density of below 700 Watts in the plasma region.

6. The method of claim 1 wherein a relatively high flow of excited effluents into the substrate processing region is maintained whereby the silicon-and-nitrogen-containing layer is made conformal during deposition.

7. The method of claim 6 wherein the relatively high flow of excited effluents into the substrate processing region is ensured by maintaining a reduced plasma power density of above or about 1000 Watts in the plasma region.

8. The method of claim 1 wherein the plasma region is separated from the substrate processing region by a showerhead.

9. The method of claim 1 wherein the inert gas comprises at least one of helium, neon, argon and xenon.

10. The method of claim 1 wherein the carbon-free silicon-containing precursor comprises N(SiH₃)₃.

11. The method of claim 1 wherein the silicon-and-nitrogen-containing layer comprises a carbon-free Si—

N—

H layer.

12. The method of claim 1 further comprising an operation of curing the silicon-and-nitrogen-containing layer by maintaining a temperature of the substrate at a curing temperature less than or about 400°

C. in an ozone-containing atmosphere to convert the silicon-and-nitrogen-containing layer into a silicon-and-oxygen-containing layer.

13. The method of claim 12 further comprising raising a temperature of the substrate to an oxygen anneal temperature above or about 600°

C. in an oxygen-containing atmosphere to convert the silicon-and-nitrogen-containing layer into a silicon-and-oxygen-containing layer.

14. The method of claim 13 wherein the oxygen-containing atmosphere comprises one or more gases selected from the group consisting of atomic oxygen, ozone, and steam (H₂O).

15. The method of claim 1 wherein the substrate is patterned and has a trench having a width of about 50 nm or less.

16. The method of claim 15 wherein the silicon-and-nitrogen-containing layer in the trench is substantially void-free.

17. The method of claim 1 wherein the plasma region is in a remote plasma system.