Method of increasing deposition rate of silicon dioxide on a catalyst

• US 20060046518A1
• Filed: 08/31/2004
• Published: 03/02/2006
• Est. Priority Date: 08/31/2004
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Derderian, Garo J., Hill, Chris W.
• Granted Patent: US 8,158,488 B2
• Time in Patent Office: Days
• US Class Current: 438/778
• CPC Class Codes: C23C 16/403 of aluminium, magnesium or beryllium
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45534 Use of auxiliary reactants other than used for contributing to the composition of the main film, e.g. catalysts, activators or scavengers
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/02203 the layer being porous
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• 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 21/316 composed of oxides or glassy oxides or oxide based glass
• CPC Class Codes: H01L 21/31683 of metallic layers, e.g. Al deposited on the body, e.g. formation of multi-layer insulating structures
• CPC Class Codes: H01L 21/31695 Deposition of porous oxides or porous glassy oxides or oxide based porous glass

Abstract

Methods for forming dielectric layers, and structures and devices resulting from such methods, and systems that incorporate the devices are provided. The invention provides an aluminum oxide/silicon oxide laminate film formed by sequentially exposing a substrate to an organoaluminum catalyst to form a monolayer over the surface, remote plasmas of oxygen and nitrogen to convert the organoaluminum layer to a porous aluminum oxide layer, and a silanol precursor to form a thick layer of silicon dioxide over the porous oxide layer. The process provides an increased rate of deposition of the silicon dioxide, with each cycle producing a thick layer of silicon dioxide of about 120 Å over the layer of porous aluminum oxide.

Claims

1. A method for forming a dielectric layer on a substrate, comprising the steps of:

exposing the substrate to an organoaluminum material to form an organoaluminum monolayer on the substrate;

exposing the organoaluminum monolayer to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

exposing the porous aluminum oxide layer to a silanol precursor to form a layer of silicon dioxide thereon.

2. The method of claim 1, wherein the active oxygen source and nitrogen comprise a remote plasma oxygen and a remote plasma nitrogen.

3. The method of claim 1, wherein the active oxygen source and nitrogen comprise about 0.01-10% by volume nitrogen, based on the total volume of oxygen and nitrogen.

4. The method of claim 1, wherein active oxygen source and nitrogen comprise about 12-16-wt-% ozone and about 0.5-1 wt-% nitrogen.

5. The method of claim 1, wherein the active oxygen source comprising nitrogen is selected from the group consisting of ozone, hydrogen peroxide vapor, water vapor, oxygen, nitrogen, nitrous oxide, nitrogen dioxide, and nitric oxide.

6. The method of claim 1, wherein the active oxygen source comprising nitrogen comprises ozone and nitrogen gas.

7. The method of claim 1, further comprising, repeating the exposing steps to form at least one additional porous aluminum oxide layer and an overlying silicon dioxide layer.

8. A method for forming a dielectric layer on a substrate, comprising the steps of:

depositing a monolayer of an organoaluminum material on the substrate;

exposing the organoaluminum monolayer to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon dioxide thereon.

9. A method for forming a dielectric layer on a substrate, comprising the steps of:

depositing an organoaluminum material onto the substrate to form a chemisorbed monolayer of the organoaluminum material;

removing non-absorbed organoaluminum material from the substrate;

exposing the organoaluminum monolayer to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon dioxide thereon.

10. A method for forming a dielectric layer on a substrate, comprising the steps of:

depositing an organoaluminum material under atomic layer deposition conditions to form a monolayer of the organoaluminum material on the substrate;

exposing the organoaluminum monolayer to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon dioxide thereon.

11. The method of claim 10, wherein the active oxygen source comprises a remote plasma oxygen, and the nitrogen comprises a remote plasma nitrogen.

12. A method for forming a dielectric layer on a substrate, comprising the steps of:

depositing a monolayer of an organoaluminum material on the substrate;

exposing the organoaluminum monolayer to a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen, based on the total volume of remote plasma oxygen and remote plasma nitrogen, to form a porous aluminum oxide layer; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon dioxide thereon.

13. A method for forming a dielectric layer on a substrate, comprising the steps of,

exposing the substrate to an organoaluminum material under atomic layer deposition conditions to form a monolayer of the organoaluminum material on the substrate;

exposing the organoaluminum monolayer to a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen to form a porous aluminum oxide layer; and

exposing the porous aluminum oxide layer to a silanol precursor to form a layer of silicon dioxide thereon.

14. A method for forming a dielectric layer on a substrate, comprising the steps of:

exposing the substrate to trimethylaluminum under atomic layer deposition conditions to form a monolayer of trimethylaluminum on the substrate;

exposing the trimethylaluminum monolayer to a remote plasma ozone and about 0.1-10% by volume remote plasma nitrogen to form a porous aluminum oxide layer, and

exposing the porous aluminum oxide layer to tris(tert-butoxy)silanol to form a layer of silicon dioxide thereon.

15. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

exposing the substrate to an organoaluminum material to form a monolayer of the organoaluminum on the substrate;

exposing the substrate to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

exposing the substrate to a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

16. The method of claim 15, further comprising:

repeating the steps of exposing the substrate to form at least one additional porous aluminum oxide layer and an overlying silicon dioxide layer.

17. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

exposing the substrate to an organoaluminum material to form a monolayer of the organoaluminum on the substrate;

purging excess organoaluminum material from the chamber;

exposing the substrate to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

exposing the substrate to a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

18. The method of claim 17, further comprising:

purging excess silanol precursor from the chamber;

repeating the steps of exposing and purging to form at least one additional porous aluminum oxide layer and an overlying silicon dioxide layer.

19. The method of claim 17, wherein the organoaluminum material is selected from the group consisting of aluminum alkyls, alkylaluminum alkoxides, and aluminum amides.

20. The method of claim 17, wherein the organoaluminum material comprises an aluminum alkyl selected from the group consisting of trimethylaluminum, triethylaluminum, and triisobutylaluminum.

21. The method of claim 17, wherein the organoaluminum material comprises triethyl(tri-sec-butoxy)dialuminum.

22. The method of claim 17, wherein the active oxygen source comprising nitrogen is selected from the group consisting of ozone, hydrogen peroxide vapor, water vapor, oxygen, nitrogen, nitrous oxide, nitrogen dioxide, and nitric oxide.

23. The method of claim 17, wherein the active oxygen source comprising nitrogen comprises ozone and nitrogen gas.

24. The method of claim 17, wherein the active oxygen source comprising nitrogen comprises a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen, based on the total volume of remote plasma oxygen and remote plasma nitrogen.

25. The method of claim 17, wherein the silanol precursor is selected from the group consisting of alkoxysilanols, alkoxyalkylsilanols, and alkoxysilanediols.

26. The method of claim 25, wherein the silanol precursor comprises a tris(alkoxy)silanol.

27. The method of claim 25, wherein the silanol precursor is selected from the group consisting of tris(tert-butoxy)silanol, tris(tert-pentyloxy)silanol, and bis(tert-alkoxy)silanediol.

28. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

exposing the substrate to an organoaluminum material under atomic layer deposition conditions to form a monolayer of the organoaluminum material on the substrate;

purging excess organoaluminum material from the chamber;

exposing the substrate to a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen to form a porous aluminum oxide layer; and

exposing the substrate to a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

29. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

bubbling an organoaluminum precursor in a gaseous form into the chamber to form an organoaluminum monolayer on the substrate;

purging excess organoaluminum precursor from the chamber;

introducing a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen into the chamber to convert the organoaluminum monolayer into an aluminum oxide layer; and

bubbling a silanol precursor in gaseous form into the chamber for about 1-60 seconds to form a layer of silicon dioxide over the porous aluminum oxide layer.

30. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber having a temperature of about 180-350°

C. and a pressure of about 0.5-10 Torr,

exposing the substrate to an organoaluminum material under atomic layer deposition conditions for about 1-5 seconds to form a monolayer of the organoaluminum material on the substrate;

purging excess organoaluminum material from the chamber;

exposing the substrate to a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen for about 6-10 seconds to form a porous aluminum oxide layer; and

exposing the substrate to a silanol precursor for about 1-60 seconds to form a layer of silicon dioxide over the porous aluminum oxide layer.

31. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

on the substrate, sequentially forming a monolayer of an organoaluminum compound, exposing the organoaluminum monolayer to an active oxygen and active nitrogen source to convert the organoaluminum monolayer to a porous aluminum oxide layer, and forming a layer of silicon dioxide over the porous aluminum oxide layer.

32. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

on the substrate, sequentially forming a monolayer of an organoaluminum compound, exposing the organoaluminum monolayer to an active oxygen and active nitrogen source to convert the organoaluminum monolayer to a porous aluminum oxide layer, and forming a layer of silicon dioxide over the porous aluminum oxide layer; and

after the sequentially forming, repeating the sequentially forming to form additional layers of silicon dioxide.

33. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially exposing the substrate to an organoaluminum material under atomic layer deposition conditions to form a monolayer of the organoaluminum material,purging the chamber with an inert gas to remove unreacted organoaluminum material, exposing the substrate to an active oxygen and active nitrogen source to convert the organoaluminum monolayer to a porous aluminum oxide layer, and exposing the substrate to a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

34. The method of claim 33, further comprising:

repeating the sequentially exposing, purging, and exposing steps to form additional layers of silicon dioxide.

35. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially exposing the substrate to an organoaluminum material to form a monolayer of the organoaluminum material, an active oxygen and active nitrogen source to convert the organoaluminum monolayer to a porous aluminum oxide layer, and a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

36. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially exposing the substrate to an organoaluminum material to form a monolayer of the organoaluminum material, a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen to convert the organoaluminum monolayer to a porous aluminum oxide layer, and a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

37. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber;

sequentially exposing the substrate to an organoaluminum material to form a monolayer of the organoaluminum material, an active oxygen and active nitrogen source to convert the organoaluminum monolayer to a porous aluminum oxide layer, and a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer, including purging the chamber after the steps of exposing the substrate to the organoaluminum material and to the silanol precursor.

38. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially pulsing into the chamber an organoaluminum material to form a monolayer of the organoaluminum material on the substrate, a remote plasma oxygen and about 0.1-10% by volume remote plasma nitrogen to convert the organoaluminum monolayer to a porous aluminum oxide layer, and a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

39-52. -52. (canceled)

53. A method for forming a dielectric layer on a substrate, comprising the steps of:

forming a monolayer of an organoaluminum material by atomic layer deposition on the substrate;

exposing the organoaluminum monolayer to an active oxygen source comprising nitrogen to form a porous aluminum oxide layer; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon dioxide thereon.

54. A method for forming a dielectric layer on a substrate, comprising the steps of:

depositing an organoaluminum catalyst by atomic layer deposition to form a monolayer of the organoaluminum catalyst over the substrate;

converting the organoaluminum catalyst monolayer to a porous aluminum oxide layer by exposing the monolayer to an active oxygen source comprising nitrogen; and

depositing a silanol material over the porous aluminum oxide layer to form a layer of silicon oxide thereon.

55. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially pulsing into the chamber;

an organoaluminum catalyst precursor to deposit a monolayer of the organoaluminum catalyst over the substrate;

an active oxygen source and an active nitrogen source to convert the organoaluminum catalyst monolayer into porous aluminum oxide; and

a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer.

56. A method for forming a dielectric layer on a substrate, comprising the steps of:

positioning a substrate within a deposition chamber; and

sequentially pulsing into the chamber;

an organoaluminum catalyst precursor to deposit a monolayer of the organoaluminum catalyst over the substrate;

an active oxygen source and an active nitrogen source to convert the organoaluminum catalyst monolayer into porous aluminum oxide; and

a silanol precursor to form a layer of silicon dioxide over the porous aluminum oxide layer; and

prior to pulsing in the active oxygen and active nitrogen sources, purging unreacted organoaluminum catalyst precursor from the chamber.

57. A method for forming a dielectric layer on a substrate, comprising the steps of:

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide; and

flowing a silanol precursor into the chamber to form a layer of silicon dioxide over the porous aluminum oxide layer.

58. A method for forming a dielectric layer on a substrate, comprising the steps of:

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

removing unreacted organoaluminum catalyst precursor from the chamber;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide;

flowing a silanol precursor into the chamber to form a layer of silicon dioxide over the porous aluminum oxide layer.

59. A method for forming a dielectric layer on a substrate, comprising the steps of:

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide;

flowing a silanol precursor into the chamber to form a layer of silicon dioxide over the porous aluminum oxide layer; and

repeating the foregoing steps as desired to form alternating layers of the porous aluminum oxide and silicon oxide to form the dielectric layer.

60. A method for forming a dielectric layer on a substrate, comprising the steps of:

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

removing unreacted organoaluminum catalyst precursor from the chamber;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide;

flowing a silanol precursor into the chamber to form a layer of silicon dioxide over the porous aluminum oxide layer; and

repeating the foregoing steps as desired to form alternating layers of the porous aluminum oxide and silicon oxide to form the dielectric layer.

61. A method for forming a dielectric layer on a substrate, comprising the steps of;

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide;

flowing a silanol precursor into the chamber to form a layer of silicon dioxide of about 100-300 Å

thick over the porous aluminum oxide layer; and

repeating the foregoing steps to form alternating layers of the porous aluminum oxide and silicon oxide as desired to form the dielectric layer.

62. A method for forming a dielectric layer on a substrate, comprising the steps of:

flowing an organoaluminum catalyst precursor into a deposition chamber containing a substrate to deposit a monolayer of the organoaluminum catalyst over the substrate by atomic layer deposition;

removing unreacted organoaluminum catalyst precursor from the chamber;

flowing oxygen and nitrogen source gases into the chamber to convert the organoaluminum catalyst monolayer into porous aluminum oxide;

flowing a silanol precursor into the chamber to form a layer of silicon dioxide of about 100-300 Å

thick over the porous aluminum oxide layer; and

repeating the foregoing steps as desired to form alternating layers of the porous aluminum oxide and silicon oxide to form the dielectric layer.