Process and apparatus for treating a workpiece with gases

• US 7,416,611 B2
• Filed: 06/18/2004
• Issued: 08/26/2008
• Est. Priority Date: 05/09/1997
• Status: Expired due to Fees

• Current Assignee: OEM Group, LLC
• Original Assignee: Semitool Incorporated (Applied Materials Incorporated)
• Inventors: Bergman, Eric J.
• Primary Examiner(s): Barr; Michael
• Assistant Examiner(s): PATEL, RITA RAMESH
• Application Number:
  US10/870,173
• Publication Number:
  US 20040221877A1
• Time in Patent Office: 1,530 Days
• Field of Search: 134/1, 134/1.3, 134/2, 134/3, 134/19, 134/25.4, 134/26, 134/30, 134/31, 134/33, 134/41, 134/902, 134/34
• US Class Current: 134/30
• CPC Class Codes: B08B 2203/005 the liquid being ozonated
• CPC Class Codes: B08B 2203/007 Heating the liquid
• CPC Class Codes: B08B 2203/0288 Ultra or megasonic jets
• CPC Class Codes: B08B 2230/01 Cleaning with steam
• CPC Class Codes: B08B 3/00 Cleaning by methods involving the use or presence of liquid or steam B08B9/00 takes precedence
• CPC Class Codes: B08B 3/02 Cleaning by the force of jets or sprays
• CPC Class Codes: B08B 3/044 using agitated containers in which the liquid and articles or material are placed by means of ultrasonic vibrations B08B3/12; cleaning casks or barrels by agitating B08B9/0817; mixers with shaking, oscillating or vibrating mechanisms B01F31/00
• CPC Class Codes: B08B 3/08 the liquid having chemical or dissolving effect substances used, see the relevant classes
• CPC Class Codes: B08B 7/00 Cleaning by methods not provided for in a single other subclass or a single group in this subclass
• CPC Class Codes: H01L 21/02052 Wet cleaning only H01L21/02085 takes precedence
• CPC Class Codes: H01L 21/02054 combining dry and wet cleaning steps H01L21/02085 takes precedence
• CPC Class Codes: H01L 21/67017 Apparatus for fluid treatment H01L21/67126, H01L21/6715 take precedence
• CPC Class Codes: H01L 21/6704 for wet cleaning or washing
• CPC Class Codes: H01L 21/67051 using mainly spraying means, e.g. nozzles
• CPC Class Codes: H01L 23/49582 Metallic layers on lead frames
• 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
• CPC Class Codes: H05K 3/3426 characterised by the leads
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 134/902 Semiconductor wafer

Abstract

In a method and apparatus for cleaning or processing a workpiece, a process gas is brought into contact with the workpiece by diffusion through a heated liquid layer on the workpiece, and by bulk transport achieved by entraining the gas in a liquid stream, spray or jet impinging on the workpiece. The process gas, which may be ozone, is entrained in the liquid via entrainment nozzles. Use of entrainment and diffusion together increases the amount of gas available for reaction at the workpiece surface, increases the reaction rate, and decreases required process times.

Claims

1. A method for cleaning a workpiece comprising:

heating a liquid to a temperature ranging from 50°

C. to about 200°

C.;

placing the workpiece into a chamber;

moving the liquid in a fluid flow line to the chamber;

entraining ozone gas into the liquid by injecting ozone gas into the liquid while the liquid is in the fluid flow line;

spraying the heated liquid onto the workpiece, with the heated liquid forming a liquid layer on the workpiece;

providing ozone gas into the spray of heated liquid, with ozone carried with the heated liquid onto the workpiece, and with ozone chemically reacting with a contaminant on the workpiece, to clean the workpiece.

2. The method of claim 1 further comprising spinning the workpiece.

3. The method of claim 1 where the liquid comprises water and hydrochloric acid, sulfuric acid, ammonium hydroxide, or hydrogen peroxide.

4. The method of claim 1 with the liquid comprising water and HF.

5. The method of claim 1 further comprising drying the workpiece by applying alcohol onto the workpiece.

6. The method of claim 1 with the liquid comprising deionized water, and wherein the liquid, ozone and a carrier gas mixture is sprayed against the workpiece.

7. The method of claim 1 with ozone gas diffusing through the liquid layer.

8. The method of claim 1 further comprising providing ozone gas into the spray of heated liquid by forming an ozone gas environment within the chamber, and with the spray of heated liquid moving through the ozone gas environment.

9. A method for cleaning a workpiece, comprising:

heating a liquid to 50-200°

C.;

entraining ozone gas into the heated liquid by mixing ozone gas with the heated liquid while the heated liquid is within a liquid reservoir;

placing the workpiece into a chamber;

moving the heated liquid from the liquid reservoir into the chamber;

directing the heated liquid onto the workpiece, with the heated liquid forming a liquid layer on the workpiece;

controlling a thickness of the liquid layer;

confining ozone gas within the chamber to form an ozone gas environment around the workpiece; and

cleaning the workpiece by chemical reaction of the ozone gas on the workpiece.

10. The method of claim 9 wherein the liquid is sprayed onto the workpiece.

11. The method of claim 9 further comprising spinning the workpiece.

12. The method of claim 9 where the liquid comprises water and a member selected from the group including one or more of hydrochloric acid, sulfuric acid, ammonium hydroxide, and hydrogen peroxide.

13. The method of claim 9 with the ozone injected into the liquid along with a carrier gas.

14. The method of claim 9 with the liquid comprising water and HF.

15. The method of claim 9 further comprising drying the workpiece by applying alcohol onto the workpiece.

16. The method of claim 9 with the liquid comprising deionized water, and wherein the liquid, ozone and a carrier gas mixture is sprayed against the workpiece.

17. The method of claim 9 further comprising spraying the heated liquid onto the workpiece through the ozone gas environment formed in the chamber, to entrain additional ozone gas into the liquid.

18. A method for cleaning at least one workpiece comprising:

heating a process liquid to 50-200°

C.;

placing the workpiece into a chamber;

moving the liquid in a fluid flow line to the chamber;

entraining ozone gas into the liquid by injecting ozone gas into the liquid while the liquid is in the fluid flow line;

applying the heated liquid onto the workpiece;

forming the liquid into a liquid layer on the workpiece;

controlling a thickness of the liquid layer on the workpiece;

rotating the workpiece;

and with the ozone chemically reacting with a contaminant on the workpiece, to clean the workpiece.

19. The method of claim 18 with the liquid including water and HF.

20. The method of claim 18 where the liquid comprises water and a member selected from hydrochloric acid, sulfuric acid, ammonium hydroxide, or hydrogen peroxide.

21. The method of claim 18 further comprising providing an ozone gas environment within the chamber and with additional ozone gas entrained in the liquid via the movement of the liquid through the ozone gas environment.

22. The method of claim 21 further comprising directing a spray of liquid out from a liquid spray nozzle in the chamber and by directing a flow of ozone gas out from a gas spray nozzle in the chamber into the spray of liquid.

23. The method of claim 21 wherein the ozone gas environment is formed in the chamber from ozone provided into the chamber with the liquid.

24. The method of claim 21 wherein the ozone gas environment is formed in the chamber by separately introducing ozone gas into the chamber as a dry gas.