Method for front end of line fabrication

• US 20050205110A1
• Filed: 05/24/2005
• Published: 09/22/2005
• Est. Priority Date: 02/26/2004
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Kao, Chien-Teh, Lu, Xinliang, Huston, Joel M., Chang, Mei, Chang, Yu, Wang, Wei W., Phan, See-Eng, Trinh, Son, Yuan, Xiaoxiong (John), Umotoy, Sal, Chou, Jing-Pei (Connie), Lai, Chiukin (Steven)
• Granted Patent: US 7,396,480 B2
• Time in Patent Office: Days
• US Class Current: 134/1.100
• CPC Class Codes: C23C 14/022 by means of bombardment with energetic particles or radiation
• CPC Class Codes: C23C 14/50 Substrate holders
• CPC Class Codes: C23C 14/541 Heating or cooling of the substrates
• CPC Class Codes: H01J 2237/2001 Maintaining constant desired temperature
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32522 Temperature
• CPC Class Codes: H01J 37/32541 Shape
• CPC Class Codes: H01J 37/32568 Relative arrangement or disposition of electrodes; moving means
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: H01L 21/02104 Forming layers deposition in general C23C; crystal growth in general C30B
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method for removing native oxides from a substrate surface is provided. In at least one embodiment, the method includes supporting the substrate surface in a vacuum chamber and generating reactive species from a gas mixture within the chamber. The substrate surface is then cooled within the chamber and the reactive species are directed to the cooled substrate surface to react with the native oxides thereon and form a film on the substrate surface. The substrate surface is then heated within the chamber to vaporize the film.

Claims

1. A method for removing native oxides from a substrate surface, comprising:

supporting the substrate surface in a vacuum chamber;

generating reactive species from a gas mixture within the chamber;

cooling the substrate surface within the chamber;

directing the reactive species to the cooled substrate surface to react with the native oxides thereon and form a film on the substrate surface; and

heating the substrate surface within the chamber to vaporize the film.

2. The method of claim 1, further comprising removing the vaporized film from the chamber.

3. The method of claim 1, wherein the film is a salt comprising nitrogen and fluorine atoms.

4. The method of claim 1, wherein the gas mixture comprises ammonia and nitrogen fluoride.

5. The method of claim 1, wherein cooling the substrate surface comprises flowing a coolant through a support assembly having the substrate surface disposed thereon and maintaining the substrate temperature below room temperature.

6. The method of claim 5, wherein the substrate temperature is maintained below about 22°

C.

7. The method of claim 1, wherein heating the substrate surface comprises positioning the substrate surface adjacent a heated gas distribution plate disposed within the vacuum chamber and maintaining the substrate temperature above about 100°

C.

8. The method of claim 7, wherein the substrate temperature is maintained at about 120°

C.

9. The method of claim 7, wherein the substrate surface is located between about 10 mils and 200 mils from the heated gas distribution plate.

10. The method of claim 1, wherein directing the reactive species to the cooled substrate surface comprises flowing the reactive species through a gas distribution plate.

11. The method of claim 10, wherein heating the substrate surface comprises heating the gas distribution plate and positioning the substrate surface in close proximity to the gas distribution plate.

12. The method of claim 11, wherein the substrate surface is heated above about 100°

C.

13. The method of claim 12, wherein heating the gas distribution plate comprises coupling a heating element to at least a portion of the gas distribution plate.

14. The method of claim 13, wherein the gas distribution plate is maintained at a temperature between about 100°

C. and about 150°

C. while heating the substrate surface within the chamber to sublimate the film.

15. The method of claim 4, wherein the gas mixture further comprises a carrier gas.

16. The method of claim 4, wherein the gas mixture comprises at least a 3 to 1 molar ratio of ammonia to nitrogen trifluoride.

17. The method of claim 16, wherein the molar ratio of ammonia to nitrogen trifluoride is between about 10:

1 and about 20;

1.

18. The method of claim 11, wherein the substrate surface is located between about 10 mils and 200 mils from the heated gas distribution plate.

19. A method for removing native oxides from a substrate surface within a single vacuum chamber, comprising:

generating a plasma of reactive species in a first section of the chamber;

cooling the substrate surface having the native oxides thereon in a second section of the chamber;

flowing the reactive species from the first section to the second section to react with the cooled substrate surface;

depositing a film on the cooled substrate surface;

moving the substrate surface to a third section of the chamber; and

heating the substrate surface in the third section of the chamber to sublimate the film.

20. A method for removing native oxides from a substrate surface within a single processing chamber, comprising:

generating a plasma of reactive species comprising nitrogen and fluorine atoms;

exposing the substrate surface to the reactive species;

cooling the substrate surface to a temperature below about 22°

C.;

depositing a film of the nitrogen and fluorine atoms on the chilled substrate surface; and

annealing the substrate surface to sublimate the film.