Low shrinkage dielectric films

• US 9,018,108 B2
• Filed: 03/15/2013
• Issued: 04/28/2015
• Est. Priority Date: 01/25/2013
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Hong, Sukwon, Tran, Toan, Mallick, Abhijit, Liang, Jingmei, Ingle, Nitin K.
• Primary Examiner(s): TRINH, MICHAEL MANH
• Application Number:
  US13/834,333
• Publication Number:
  US 20140213070A1
• Time in Patent Office: 774 Days
• Field of Search: 438/787, 438/788, 438/778, 438/792, 257/E21.278
• US Class Current: 438/787
• 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 16/401 containing silicon
• 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 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45574 Nozzles for more than one gas
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• 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 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• 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
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma

Abstract

Methods of forming a dielectric layer on a substrate are described, and may include introducing a first precursor into a remote plasma region fluidly coupled with a substrate processing region of a substrate processing chamber A plasma may be formed in the remote plasma region to produce plasma effluents. The plasma effluents may be directed into the substrate processing region. A silicon-containing precursor may be introduced into the substrate processing region, and the silicon-containing precursor may include at least one silicon-silicon bond. The plasma effluents and silicon-containing precursor may be reacted in the processing region to form a silicon-based dielectric layer that is initially flowable when formed on the substrate.

Claims

1. A method of forming a dielectric layer on a substrate in a substrate processing region of a processing chamber, the method comprising:

introducing a first precursor into a remote plasma region fluidly coupled with the substrate processing region while forming a plasma in the remote plasma region to produce plasma effluents;

directing the plasma effluents into the substrate processing region;

introducing a silicon-containing precursor into the substrate processing region, wherein the silicon-containing precursor includes at least one silicon-silicon bond; and

reacting the plasma effluents and silicon-containing precursor in the substrate processing region to form a silicon-based dielectric layer that is initially flowable when formed on the substrate, wherein the processing chamber is maintained at a temperature from about 30°

C. to about −

30°

C., and wherein the pressure within the processing chamber is maintained so the reacting operation occurs at or about the condensation point of the silicon-containing precursor.

2. The method of claim 1, wherein the silicon-containing precursor includes at least two silicon-silicon bonds.

3. The method of claim 1, wherein the first precursor includes one or more precursors selected from the group consisting of ammonia, nitrogen, H₂, Ar, and He.

4. The method of claim 1, wherein the plasma effluents and silicon-containing precursor are introduced into the processing region through a showerhead configured to maintain separation of the precursors so that they do not contact each other until they enter the substrate processing region.

5. The method of claim 4, wherein the substrate is maintained at a distance less than or at about 3 inches from the showerhead.

6. The method of claim 1, wherein the substrate processing region is plasma-free during the deposition process.

7. The method of claim 1, wherein the silicon-containing precursor has the formula Si_xH_y, wherein x is greater than or equal to 2, and y is 2x+n or greater, wherein n is any number less than or equal to 2, and wherein the silicon-containing precursor is introduced into the processing region in a substantially vapor phase.

8. The method of claim 1, wherein the method is performed at a temperature of less than or equal to about 30°

C.

9. The method of claim 1, wherein the method is performed at a pressure of less than or equal to about 5 Torr.

10. The method of claim 1, whrerein the as-formed film has a density greater than or equal to about 1.4 g/cc.

11. The method of claim 1, further comprising stopping the introduction of the silicon-containing precursor after the silicon-based dielectric layer is formed, and continuing to direct the plasma effluents of the first precursor into the substrate processing region to densify the formed dielectric layer.

12. The method of claim 1, further comprising annealing the formed silicon-based dielectric layer.

13. The method of claim 12, wherein the formed silicon-based dielectric layer shrinks by less than about 20% during the annealing.

14. A method of forming a dielectric layer on a substrate in a substrate processing region of a processing chamber, the method comprising:

introducing a first precursor into a remote plasma region fluidly coupled with the substrate processing region while forming a plasma in the remote plasma region to produce plasma effluents;

directing the plasma effluents into the substrate processing region;

introducing a silicon-containing precursor into the substrate processing region, wherein the silicon-containing precursor includes at least one silicon-silicon bond;

reacting the plasma effluents and silicon-containing precursor in the substrate processing region to form a silicon-based dielectric layer that is initially flowable when formed on the substrate, wherein the processing chamber is maintained at a temperature from about 30°

C. to about −

30°

C., and wherein the pressure within the processing chamber is maintained so the reacting operation occurs at or about the condensation point of the silicon-containing precursor; and

curing the formed silicon-based dielectric layer with at least one additional precursor.

15. The method of claim 14, wherein the at least one additional precursor comprises an oxygen-containing precursor, a nitrogen-containing precursor, or a carbon-containing precursor.

16. The method of claim 14, further comprising directing the plasma effluents into the substrate processing region to densify the cured dielectric layer.

17. The method of claim 14, wherein the silicon-containing precursor has the formula Si_xH_y, wherein x is greater than or equal to 2, and y is 2x+n or greater, wherein n is any number less than or equal to 2, and wherein the silicon-containing precursor is introduced into the processing region in a substantially vapor phase.

18. The method of claim 14, wherein the precursors introduced into the processing chamber to form the silicon-based dielectric layer consist of one or more inert precursors and a silicon-containing precursor consisting of silicon-silicon and silicon-hydrogen containing bonds.

19. The method of claim 14, further comprising annealing the formed silicon-based dielectric layer.

20. The method of claim 14, wherein the formed silicon-based dielectric layer shrinks by less than about 20% during the annealing.