Mask cleaning

• US 10,459,352 B2
• Filed: 08/31/2015
• Issued: 10/29/2019
• Est. Priority Date: 08/31/2015
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chang, Shu-Hao, Chen, Norman, Chen, Jeng-Horng, Kau, Kuo-Chang, Chien, Ming-Chin, Chien, Shang-Chieh, Yen, Anthony, Huang, Kevin
• Primary Examiner(s): Persaud, Deoram
• Application Number:
  US14/840,581
• Publication Number:
  US 20170060005A1
• Time in Patent Office: 1,520 Days
• CPC Class Codes: G03F 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70925 Cleaning, i.e. actively freeing apparatus from pollutants, e.g. using plasma cleaning

Abstract

A lithography system includes a load lock chamber comprising an opening configured to receive a mask, an exposure module configured to expose a semiconductor wafer to a light source through use of the mask, and a cleaning module embedded inside the lithography tool, the cleaning module being configured to clean carbon particles from the mask.

Claims

1. A lithography system comprising:

a load lock chamber comprising an opening configured to receive a mask;

an exposure module configured to expose a semiconductor wafer to a light source through use of the mask; and

a cleaning module embedded inside the lithography tool, the cleaning module being configured to clean carbon particles from the mask;

wherein the cleaning module is integrated into the load lock chamber.

2. The lithography tool of claim 1, wherein the lithography tool is an Extreme Ultra-Violet (EUV) lithography tool, the mask is an EUV mask, and the light source is an EUV light source.

3. The lithography system of claim 1, wherein the cleaning module is configured to produce hydrogen radicals.

4. The lithography system of claim 3, wherein the cleaning module comprises:

a filament configured to be heated to heat to a temperature greater than 1900 degrees Celsius; and

a gas source configured to pass hydrogen gas over the filament to produce the hydrogen radicals.

5. The lithography system of claim 1, wherein the cleaning module is configured to produce a plasma gas including at least one of:

hydrogen, oxygen, nitrogen, argon, helium, fluorine, and chlorine.

6. The lithography system of claim 1, wherein the cleaning module comprises one of:

a laser decomposition cleaning system, an ultraviolet ozone cleaning system, and an electron-stimulated desorption cleaning system.

7. The lithography system of claim 1, wherein the cleaning module comprises an ultrasonic wave producer positioned to create wave within a gas.

8. The lithography system of claim 1, further comprising a library module configured to store a plurality of masks, the library being positioned between the load lock chamber and the exposure tool, wherein the cleaning module comprises a pump configured to pump gas out of the cleaning module.

9. A lithography system comprising:

an opening;

an exposure module to expose a wafer to a light source;

a robotic mechanism to move a mask between the opening and the exposure module;

a cleaning module; and

a control system comprising a processor and a memory comprising machine readable instructions that when executed by the processor to;

cause the robotic mechanism to receive the mask through the opening;

cause the robotic mechanism to place the mask in the cleaning module; and

cause the cleaning module to clean the mask;

wherein the cleaning module is integrated into a load lock chamber of the lithography system.

10. The system of claim 9 wherein the control system is further to create a vacuum in the load lock chamber to after receiving the mask.

11. The system of claim 9, wherein the control system is further to cause the cleaning module to:

heat a filament; and

pass a gas over the filament at a flow rate greater than 2000 sccm.

12. The system of claim 9, wherein the control system is further to cause the cleaning module to:

apply an Alternating Current (AC) signal to a plasma source, the AC signal having a voltage within a range of about 1 to 30 kilovolts and a frequency within a range of 1-40 kilohertz; and

pass a gas over the filament at a flow rate greater than 2000 sccm.

13. The system of claim 9, wherein the control system is further to cause the cleaning module to:

pass a gas over a plasma source at a flow rate greater than 2000 sccm; and

generate a plasma gas from the gas using a plasma source.

14. The system of claim 13, wherein the control system is further to cause the cleaning module to:

create wave within the plasma gas using an ultrasonic wave producer.

15. A method comprising:

loading a mask into a lithography tool;

while the mask is in the lithography tool, causing the mask to be within a vacuum environment of a cleaning module;

using a gas to remove carbon particles from a surface of the mask while the mask is in the lithography tool; and

while keeping the mask in a vacuum environment, transferring the mask to an exposure module for implementing a lithography exposure process using the mask;

wherein the cleaning module is integrated into a load lock chamber of the lithography tool.

16. The method of claim 15, wherein the gas comprises at least one of:

oxygen, nitrogen, hydrogen, an inert gas, and a halogen gas.

17. The method of claim 16, further comprising heating the gas to a temperature within a range of about 350 to 900 degrees Fahrenheit.

18. The method of claim 15, wherein using a gas to remove the carbon particles from the surface of the mask comprises applying an Alternating Current (AC) signal to a plasma source.

19. The method of claim 18, wherein using a gas to remove the carbon particles from the surface of the mask comprises passing a gas over the filament at a flow rate greater than 2000 sccm.

20. The method of claim 15, wherein using a gas to remove the carbon particles from the surface of the mask comprises creating wave within the gas using an ultrasonic wave producer.