Apparatus and method for delivering a treatment liquid and ozone to treat the surface of a workpiece

• US 20010042555A1
• Filed: 04/18/2001
• Published: 11/22/2001
• Est. Priority Date: 05/09/1997
• Status: Active Grant

• Current Assignee: OEM Group, LLC
• Original Assignee: Semitool Incorporated (Applied Materials Incorporated)
• Inventors: Bergman, Eric J., Hess, Mignon P.
• Granted Patent: US 6,601,594 B2
• Time in Patent Office: Days
• US Class Current: 134/1.3
• CPC Class Codes: B08B 2203/005 the liquid being ozonated
• CPC Class Codes: B08B 2230/01 Cleaning with steam
• CPC Class Codes: B08B 3/02 Cleaning by the force of jets or sprays
• 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 21/6704 for wet cleaning or washing
• CPC Class Codes: Y10S 134/902 Semiconductor wafer

Abstract

An apparatus for supplying a mixture of a treatment liquid and ozone for treatment of a surface of a workpiece, and a corresponding method are set forth The preferred embodiment of the apparatus comprises a liquid supply line that is used to provide fluid communication between a reservoir containing the treatment liquid and a treatment chamber housing the workpiece. A heater is disposed to heat the workpiece, either directly or indirectly. Preferably, the workpiece is heated by heating the treatment liquid that is supplied to the workpiece. One or more nozzles accept the treatment liquid from the liquid supply line and spray it onto the surface of the workpiece while an ozone generator provides ozone into an environment containing the workpiece.

Claims

1. A method for treating a workpiece comprising the steps of:

(a) contacting a workpiece having a thin aqueous liquid boundary layer on the surface thereof with ozone whereby the ozone can diffuse through the boundary layer to provide a diffusion-controlled reaction between the ozone and the surface of the workpiece, and

(b) reacting the ozone with the surface of the workpiece while the surface of workpiece is at an elevated temperature.

2. A method as defined in

claim 1

wherein the thin aqueous liquid boundary layer is established on the surface of the workpiece by spraying aqueous liquid onto said surface and rotating the workpiece at a speed of rotation sufficient to control the thickness of the boundary layer.

3. A method as defined in

claim 1

wherein the thin aqueous liquid boundary layer is established on the surface of the workpiece by supplying aqueous liquid in vapor form whereby the vapor condenses on the surface of the workpiece to form a thin aqueous liquid boundary layer thereon.

4. A method as defined in

claim 1

wherein the thin aqueous liquid boundary layer is established by spraying a mixture of ozone and aqueous liquid onto the surface of the workpiece whereby the ozone separates from said aqueous liquid as the aqueous liquid forms said boundary layer.

5. A method as defined in

claim 1

wherein the workpiece is maintained at an elevated temperature by heating the workpiece.

6. A method as defined in

claim 5

wherein the workpiece is heated by contacting the workpiece with a heated gas.

7. A method as defined in

claim 6

wherein the gas is nitrogen.

8. A method as defined in

claim 6

wherein the gas is ozone.

9. A method as defined in

claim 5

wherein the workpiece is heated by contacting the workpiece with said aqueous liquid maintained at an elevated temperature.

10. A method for treating a workpiece comprising the steps of:

(a) depositing on the surface of the workpiece a thin aqueous liquid boundary layer whereby ozone can diffuse through the boundary layer, and

(b) contacting the surface of the workpiece with ozone gas while the surface of the workpiece is at an elevated temperature whereby the ozone reacts with the surface of the workpiece by way of a diffusion-controlled reaction.

11. A method as defined in

claim 10

wherein the thin aqueous liquid boundary layer is established on the surface of the workpiece by spraying aqueous liquid onto said surface and rotating the workpiece at a speed of rotation sufficient to control the thickness of the boundary layer.

12. A method as defined in

claim 10

wherein the thin aqueous liquid boundary layer is established on the surface of the workpiece by supplying aqueous liquid in vapor form whereby the vapor condenses on the surface of the workpiece to form a thin aqueous liquid boundary layer thereon.

13. A method as defined in

claim 10

wherein the thin liquid boundary layer is established by spraying a mixture of ozone and aqueous liquid onto the surface of the workpiece whereby the ozone separates from said aqueous liquid as the aqueous liquid forms said boundary layer.

14. A method as defined in

claim 10

wherein the workpiece is maintained at an elevated temperature by heating the workpiece.

15. A method as defined in

claim 14

wherein the workpiece is heated by contacting the workpiece with a heated gas.

16. A method as defined in

claim 14

wherein the surface of the workpiece is maintained at an elevated temperature by contacting the workpiece with said aqueous liquid at an elevated temperature.

17. A method for treating a workpiece comprising the steps of:

(a) spraying the surface of the workpiece with aqueous liquid while rotating the workpiece to form a thin aqueous liquid boundary layer on the surface thereof, said boundary layer being sufficiently thin to permit ozone to diffuse therethrough, and

(b) contacting the surface of the workpiece with ozone gas while the surface of the workpiece is at an elevated temperature whereby the ozone reacts with the surface of the workpiece by way of a diffusion-controlled reaction.