Method for directional deposition using a gas cluster ion beam
View Patent ↗A method for depositing material on a substrate is described. The method comprises directionally depositing a thin film on one or more surfaces of a substrate using a gas cluster ion beam (GCIB) formed from a source of precursor to the thin film, wherein the deposition occurs on surfaces oriented substantially perpendicular to the direction of incidence of the GCIB, and deposition is substantially avoided on surfaces oriented substantially parallel to the direction of incidence.
1. A method for depositing material on a substrate having one or more structures that include a trench, via, contact, capacitor trench, or other recessed feature formed in said substrate and that define a plurality of surfaces including one or more first surfaces lying substantially parallel to a first plane and one or more second surfaces lying substantially perpendicular to said first plane, said one or more first surfaces including a recessed bottom surface of said one or more structures and said one or more second surfaces including opposing recessed sidewall surfaces of said one or more structures, the method comprising:
directing a gas cluster ion beam (GCIB) formed from a source of precursor to a thin film toward said substrate with a direction of incidence, said directing said GCIB further comprises:
generating said GCIB in a reduced-pressure environment from a pressurized gas mixture having said source of precursor at a stagnation pressure in a stagnation chamber,
selecting a beam size of said GCIB using a final beam aperture,
selecting a beam acceleration potential,
selecting a beam dose,
accelerating said GCIB according to said beam acceleration potential using one or more high voltage electrodes, and
irradiating said accelerated GCIB onto said substrate according to said beam dose; and
orienting said substrate relative to said direction of incidence such that said first plane is substantially perpendicular to said direction of incidence and selecting and/or modifying one or more GCIB properties selected from the group consisting of said stagnation pressure, said beam size, and said beam acceleration potential to effect a directionally deposition of said thin film on said one or more first surfaces oriented substantially perpendicular to said direction of incidence including on said recessed bottom surface, while substantially reducing or avoiding deposition of said thin film on said one or more second surfaces oriented substantially parallel to said direction of incidence including on said opposing recessed sidewall surfaces and relative to said one or more first surfaces.
2. The method of claim 1 , wherein a thickness of said thin film that is formed on said one or more first surfaces is achieved by selecting said GCIB dose.
3. The method of claim 1 , further comprising:
adjusting the orientation of said substrate relative to said direction of incidence to directionally deposit said thin film on one or more of said plurality of surfaces different than said one or more first surfaces.
4. The method of claim 1 , further comprising:
directing another gas cluster ion beam (GCIB) formed from another source of precursor to another thin film with said direction of incidence to directionally deposit said another thin film on said one or more first surfaces of said substrate, wherein the material composition of said another thin film is different than the material composition of said thin film.
5. The method of claim 4 , wherein said directing said GCIB and said another GCIB toward said substrate to directionally deposit said thin film and said another thin film are alternatingly and sequentially performed.
6. The method of claim 1 , wherein said thin film comprises a silicon-containing material.
7. The method of claim 6 , wherein said source of precursor to said silicon-containing material comprises silane (SiH 4 ), disilane (Si 2 H 6 ), dichlorosilane (SiH 2 Cl 2 ), trichlorosilane (SiCl 3 H), diethylsilane (C 4 H 12 Si), trimethylsilane (C 3 H 10 Si), silicon tetrachloride (SiCl 4 ), silicon tetrafluoride (SiF 4 ), or a combination of two or more thereof.
8. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises a germanium-containing material, a carbon-containing material, an oxygen-containing material, a hydrogen-containing material, a nitrogen-containing material, a fluorine-containing material, a sulfur-containing material, a boron-containing material, a phosphorous-containing material, or an arsenic-containing material, or a combination of two or more thereof.
9. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises a hydrocarbon gas having the formula C x H y , wherein x and y are integers greater than or equal to unity.
10. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises a fluorocarbon gas having the formula C x F y , wherein x and y are integers greater than or equal to unity.
11. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises a hydrofluorocarbon gas having the formula C x H y F z , wherein x, y and z are integers greater than or equal to unity.
12. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises methane (CH 4 ) or carbon tetrafluoride (CF 4 ) or a combination thereof.
13. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises H 2 , N 2 , NH 3 , NF 3 , O 2 , CO, CO 2 , NO, N 2 O, or NO 2 , or a combination of two or more thereof.
14. The method of claim 7 , wherein said source of precursor to said silicon-containing material further comprises sulfur hexafluoride (SF 6 ), boron trifluoride (BF 3 ), diborane (B 2 H 6 ), phosphine (PH 3 ), PF 5 , arsine (AsH 3 ), or AsF 5 , or a combination of two or more thereof.
15. The method of claim 7 , wherein said source of precursor to said silicon-containing material comprises germane (GeH 4 ), digermane (Ge 2 H 6 ), dichlorogermane (GeH 2 Cl 2 ), trichlorogermane (GeCl 3 H), diethylgermane (C 4 H 12 Ge), trimethylgermane (C 3 H 10 Ge), germanium tetrachloride (GeCl 4 ), germanium tetrafluoride (GeF 4 ), or a combination of two or more thereof.
16. The method of claim 1 , wherein said thin film comprises a fluorocarbon-containing material.
17. The method of claim 1 , wherein said thin film comprises a tungsten-containing material.
18. The method of claim 1 , wherein said directional deposition of said thin film further comprises:
continuing the directing and irradiating to effect a directional filling of said trench, via, contact, capacitor trench, or other feature formed in said substrate from bottom-to-top by further directionally depositing on said thin film from said recessed bottom surface to a top surface adjacent the opposing recessed sidewall surfaces of said one or more structures.
19. The method of claim 1 , further comprising:
directionally depositing said thin film on an electronic device selected from the group consisting of an interconnect structure, a transistor, or a capacitor.
20. The method of claim 1 , further comprising:
directionally depositing said thin film on a micro-electromechanical device or a nano-electromechanical device.