Method for depositing atomized materials onto a substrate utilizing light exposure for heating

• US 6,174,651 B1
• Filed: 01/14/1999
• Issued: 01/16/2001
• Est. Priority Date: 01/14/1999
• Status: Expired due to Fees

• Current Assignee: STEAG RTP Systems, Inc. (KSBG Kommunale Beteiligungsgesellschaft GmbH & Company KG)
• Original Assignee: STEAG RTP Systems, Inc. (KSBG Kommunale Beteiligungsgesellschaft GmbH & Company KG)
• Inventors: Thakur, Randhir P. S.
• Primary Examiner(s): Young, Christopher G.
• Application Number:
  US09/229,872
• Time in Patent Office: 733 Days
• Field of Search: 430/311, 430/327, 430/330, 427/58, 427/96, 427/248.1, 427/255.6
• US Class Current: 430/272.1
• CPC Class Codes: G03F 7/16 Coating processes; Apparatus therefor applying coatings to base materials in general B05; applying photosensitive compositions to base for photographic purposes G03C1/74
• CPC Class Codes: G03F 7/162 Coating on a rotating support, e.g. using a whirler or a spinner
• CPC Class Codes: G03F 7/168 Finishing the coated layer, e.g. drying, baking, soaking

Abstract

The present invention is generally directed to a process and a system for forming photoresist coatings on a semiconductor wafer. In particular, according to the present invention, a solution containing a photoresist material is atomized in a reaction vessel and directed towards a semiconductor wafer. The semiconductor wafer can be preheated. The atomized liquid is heated, such as by being exposed to light energy which causes the photoresist material to form a coating on the substrate.

Claims

1. A process for depositing a photoresist material on a semiconductor wafer comprising the steps of:

atomizing a solution into liquid droplets, said solution containing a photoresist material;

exposing said liquid droplets to light energy such that the droplets are heated to a temperature sufficient for liquids contained in said droplets to evaporate;

directing said heated liquid droplets onto a preheated semiconductor wafer in a thermal processing chamber such that said photoresist material forms a solid coating on said semiconductor wafer, said semiconductor wafer being preheated to a temperature of at least 50°

C.; and

engraving a predetermined pattern into said solid coating made from said photoresist material, said pattern being designed to facilitate the formation of an integrated circuit.

2. A process as defined in claim 1, wherein said liquid droplets are heated to a temperature of from about 100°

C. to about 700°

C. in forming said solid coating.

3. A process as defined in claim 1, wherein said liquid droplets have a diameter of at least 10 microns.

4. A process as defined in claim 1, wherein said liquid droplets are atomized by passing said solution through a nozzle, said nozzle being heated.

5. A process as defined in claim 1, wherein said semiconductor wafer is rotated during the formation of said solid coating.

6. A process as defined in claim 1, wherein said semiconductor wafer is vibrated during the formation of said solid coating.

7. A process as defined in claim 1, wherein said semiconductor wafer is exposed to ultraviolet light rays during said process.

8. A process as defined in claim 1, wherein said solid coating has a thickness of at least 1,000 angstroms.

9. A process as defined in claim 1, wherein said semiconductor wafer has been precoated with a spincoated layer of said photoresist material prior to forming said solid coating of said photoresist material on said semiconductor wafer.

10. A process as defined in claim 1, further comprising the step of spin coating an additional layer of said photoresist material on said formed solid coating.

11. A process as defined in claim 1, wherein said liquid droplets are heated to a temperature sufficient to remove substantially all of any solvent that may be contained in said liquid droplets during formation of said solid coating.

12. A process for depositing a photoresist material onto a semiconductor wafer comprising the steps of:

atomizing a solution into liquid droplets, said solution containing a photoresist material;

exposing said droplets to light energy within said thermal processing chamber, said light energy heating said droplets an amount sufficient for liquids contained in said droplets within said solution to evaporate; and

directing said liquid droplets exposed to said light energy onto a semiconductor wafer in a thermal processing chamber such that said photoresist material forms a solid coating on said semiconductor wafer.

13. A process as defined in claim 12, further comprising the step of moving said semiconductor wafer during formation of said coating in a manner that promotes coating thickness uniformity.

14. A process as defined in claim 13, wherein said semiconductor wafer is rotated during the formation of said solid coating.

15. A process as defined in claim 13, wherein said semiconductor wafer is vibrated during formation of said coating.

16. A process as defined in claim 13, wherein said semiconductor wafer is subjected to ultrasonic energy during formation of said coating.

17. A process as defined in claim 12, wherein said light energy comprises thermal light energy.

18. A process as defined in claim 12, wherein said liquid droplets are deposited onto said semiconductor wafer at a temperature within a first temperature range and, after deposition, said coating is exposed to a temperature within a second temperature range, said second temperature range being higher than said first temperature range.

19. A process as defined in claim 12, wherein said semiconductor wafer is preheated by an electrical resistance heater.

20. A process as defined in claim 12, further comprising the step of preheating said semiconductor wafer prior to directing said droplets onto said semiconductor wafer.

21. A process for depositing a photoresist material onto a semiconductor wafer comprising the steps of:

atomizing a solution into liquid droplets, said solution containing a photoresist material, said droplets having a diameter of from about 10 microns to about 100 microns;

exposing said liquid droplets to light energy, said light energy heating said liquid droplets an amount sufficient for liquids contained in said droplets to evaporate, said light energy comprising thermal light energy;

directing said liquid droplets exposed to said light energy onto a preheated semiconductor wafer in a thermal processing chamber such that said photoresist material forms a solid coating on said semiconductor wafer, said semiconductor wafer being preheated to a temperature of at least 50°

C.; and

moving said semiconductor wafer during formation of said coating in a manner that promotes coating thickness uniformity.

22. A process as defined in claim 21, wherein said liquid droplets are heated to a temperature of from about 100°

C. to about 500°

C. during formation of said coating.

23. A process as defined in claim 21, wherein said semiconductor wafer is vibrated during formation of said coating.

24. A process as defined in claim 21, wherein said semiconductor wafer is rotated during formation of said coating.

25. A process as defined in claim 21, wherein said semiconductor wafer is exposed to ultraviolet radiation during formation of said coating.

26. A process as defined in claim 25, wherein said semiconductor wafer is preheated to at least 50°

C. using light energy.

27. A process as defined in claim 21, wherein said solution is atomized by being fed through at least one heated nozzle.

28. A process as defined in claim 21, wherein said formed coating has a thickness of at least 500 angstroms.

29. A process as defined in claim 21, wherein said liquid droplets are heated to a temperature sufficient to remove substantially all of any solvents that may be contained within said liquid droplets during formation of said solid coating.