Method for increasing the penetration depth of material infusion in a substrate using a gas cluster ion beam

• US 7,883,999 B2
• Filed: 01/25/2008
• Issued: 02/08/2011
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: TEL Manufacturing and Engineering of America, Inc.
• Original Assignee: TEL Epion Inc. (Tokyo Electron Limited)
• Inventors: Tetreault, Thomas G., Shao, Yan, Hautala, John J.
• Primary Examiner(s): Landau; Matthew C
• Assistant Examiner(s): Hall; Jessica
• Application Number:
  US12/020,094
• Publication Number:
  US 20090191696A1
• Time in Patent Office: 1,110 Days
• Field of Search: 438/185, 438/914, 438/37, 438/232, 438371-375, 438/45, 438/181, 438473-474, 438/510, 438/514, 438/519, 438/522, 438/527, 438530-531, 438/151, 257E21135-E21153
• US Class Current: 438/519
• CPC Class Codes: H01J 2237/0812 Ionized cluster beam [ICB] sources
• CPC Class Codes: H01L 21/26506 in group IV semiconductors
• CPC Class Codes: H01L 21/26513 of electrically active species
• CPC Class Codes: H01L 21/26566 of a cluster, e.g. using a gas cluster ion beam

Abstract

A method for infusing material below the surface of a substrate is described. The method comprises modifying a surface condition of a surface on a substrate to produce a modified surface layer, and thereafter, infusing material into the modified surface in the substrate by exposing the substrate to a gas cluster ion beam (GCIB) comprising the material.

Claims

1. A method for infusing material within a surface of a substrate, comprising:

modifying a surface condition of a surface on a substrate to produce a modified surface layer by exposing said substrate to one or more pre-treatment gas cluster ion beams (GCIBs) comprising a noble gas element; and

thereafter, infusing material into said modified surface layer in said substrate by exposing said substrate to a gas cluster ion beam (GCIB) comprising said material,

wherein said modifying said surface condition effects a deeper penetration of said material into said substrate during said infusing relative to infusing said material without said modifying.

2. The method of claim 1, wherein said substrate comprises a crystalline material, and said modifying said surface condition of said surface of said substrate causes amorphization of said surface to produce said modified surface layer.

3. The method of claim 1, wherein said noble gas element is argon.

4. The method of claim 1, wherein said modifying said surface condition of said surface on said substrate further comprises:

exposing said substrate to an ion beam to cause ion implantation, said ion beam is substantially composed of non-clustered ions;

or

exposing said substrate to plasma to cause plasma immersion ion implantation;

or a combination thereof.

5. The method of claim 1, wherein said modifying comprises:

maintaining a reduced-pressure environment around a substrate holder for holding said substrate having said surface;

holding said substrate securely within said reduced-pressure environment;

providing to said reduced-pressure environment said one or more pre-treatment GCIBs from a pressurized gas mixture comprising said noble gas element;

accelerating each of said one or more pre-treatment GCIBs to a pre-treatment beam energy; and

irradiating each of said one or more accelerated pre-treatment GCIBs onto at least a portion of said surface of said substrate to alter said surface condition of said surface.

6. The method of claim 5, wherein one or more of said pre-treatment beam energies is greater than about 5 keV.

7. The method of claim 5, wherein one or more of said pre-treatment beam energies is greater than about 10 keV.

8. The method of claim 5, wherein one or more of said pre-treatment beam energies is greater than about 20 keV.

9. The method of claim 5, wherein one or more of said pre-treatment beam energies is greater than about 30 keV.

10. The method of claim 1, wherein said one or more pre-treatment GCIBs contain said noble gas element and do not contain said material.

11. The method of claim 1, wherein said

one or more pre-treatment GCIBs consist of said noble gas element.

12. The method of claim 1, wherein said

one or more pre-treatment GCIBs consist of argon.

13. The method of claim 1, wherein said infusing said material comprises:

maintaining a reduced-pressure environment around a substrate holder for holding said substrate having said surface;

holding said substrate securely within said reduced-pressure environment;

providing to said reduced-pressure environment said GCIB from a pressurized gas mixture comprising said material;

accelerating said GCIB to an infusion beam energy; and

irradiating said accelerated GCIB onto at least a portion of said modified surface layer of said substrate to infuse said material into said modified surface layer.

14. The method of claim 13, wherein said infusion beam energy is less than about 10 keV.

15. The method of claim 13, wherein said material comprises boron (B), phosphorous (P), arsenic (As), or antimony (Sb), or any combination of two or more thereof.

16. The method of claim 1, wherein a first of said one or more pre-treatment GCIBs has a beam energy greater than about 10 keV, and wherein said GCIB comprising said material has a beam energy less than said beam energy of said first of said one or more pre-treatment GCIBs.

17. The method of claim 16, wherein said first of said one or more pre-treatment GCIBs has a beam energy greater than about 20 keV, and wherein said GCIB comprising said material has a beam energy less than about 10 keV.

18. The method of claim 16, wherein each of said one or more pre-treatment GCIBs subsequent to said first has a lower beam energy than a beam energy of a preceding one of said one or more pre-treatment GCIBs.

19. A method for infusing material within a surface of a substrate, comprising:

treating a surface on a substrate using a first GCIB consisting essentially of a noble gas element and having a first beam energy in order to modify a surface condition of said surface on said substrate to produce a modified surface layer; and

thereafter, infusing material into said modified surface layer in said substrate by exposing said substrate to a second GCIB comprising said material and having a second beam energy that is less than the first beam energy;

wherein said treating effects a deeper penetration of said material into said substrate during said infusing relative to infusing said material without said treating.

20. The method of claim 19, wherein said first GCIB consists of a noble gas element, and wherein said first beam energy is greater than or equal to about 10 keV.

21. The method of claim 19, wherein said second beam energy is less than or equal to about 10 keV.

22. The method of claim 19, further comprising:

smoothing said modified surface on said substrate prior to said infusing said material.

23. The method of claim 19, further comprising:

post-treating said substrate containing said infused material by treating said substrate with a third GCIB, treating said substrate with elevated temperature thermal annealing, treating said substrate with pulsed laser beam annealing, or treating said substrate with pulsed electron beam annealing, or any combination of two or more thereof.

24. The method of claim 19, further comprising:

forming a patterned mask layer on said substrate prior to treating said surface on said substrate using said first GCIB in order to cause patterning of the distribution of said modified surface layer; and

removing said patterned mask layer prior to infusing said material into said patterned modified surface layer by exposing said substrate to said second GCIB in order to cause patterning of the distribution of an infusion depth of said material, or an infusion dose of said material, or both.

25. The method of claim 19, wherein said first beam energy is greater than about 10 keV and said second beam energy is less than about 10 keV.