Highly efficient automatic particle cleaner method for EUV systems

Patent metadata

Field	Value
Publication number	US-11520246-B1
Application number	US-202117461456-A
Country	US
Kind code	B1
Filing date	Aug 30, 2021
Priority date	Aug 30, 2021
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

In a method of cleaning a lithography system, during idle mode, a stream of air is directed, through a first opening, into a chamber of a wafer table of an EUV lithography system. One or more particles is extracted by the directed stream of air from surfaces of one or more wafer chucks in the chamber of the wafer table. The stream of air and the extracted one or more particle are drawn, through a second opening, out of the chamber of the wafer table.

First claim

What is claimed is:

1. A method, comprising:
during idle mode:
directing one or more pressurized jets of air, entering through a first opening into a chamber of a wafer table of an EUV lithography system, to impinge onto walls and one or more wafer chucks in the chamber;
extracting one or more particles by the one or more pressurized jet of air from surfaces of the walls and the one or more wafer chucks in the chamber of the wafer table;
drawing the extracted one or more particle and the entered one or more jets of air, through a second opening, out of the chamber of the wafer table;
directing the entered air and the extracted one or more particles as a first stream of air through an air filter system outside the chamber of the wafer table at the second opening;
collecting the one or more particles by the air filter system to clean the first stream of air;
detecting a number of particles in the cleaned first stream of air after the air filter system; and
recycling the cleaned first stream of air through the first opening into the chamber of the wafer table when the number of particles in the first stream of air is below a first threshold.

2. The method of claim 1 , wherein the one or more pressurized jets of air are generated by a first air conducting system, the method further comprising:
drawing the extracted one or more particles and the entered air by a second air conducting system coupled the chamber of the wafer table, wherein the second air conducting system is connected to the second opening.

3. The method of claim 1 , wherein the one or more pressurized jets of air comprises a solvent carried by the one or more pressurized jets of air, and wherein the air filter system comprises two or more air filters, the method further comprising:
dissolving organic material contamination on the walls and surfaces of the one or more wafer chucks by the solvent, wherein the organic material contamination is carried by the first stream of air through the air filter system; and
extracting the organic material contamination by one of the two or more air filters.

4. The method of claim 1 , further comprising:
directing two or more pressurized jets of air, through two or more nozzles that are arranged at two or more different directions, at the first opening;
directing the two or more pressurized jets of air at a plurality of locations of the walls and the surfaces of the one or more wafer chucks by moving the two or more nozzles to change two or more directions of the pressurized jets of air; and
adjusting flow rates of the two or more pressurized jets of air.

5. The method of claim 4 , wherein at least a first nozzle of the two or more nozzles is mounted above a first wafer chuck of the one or more wafer chucks, the method comprising:
directing the pressurized jet of air from the first nozzle to a top of the first wafer chuck.

6. The method of claim 1 , further comprising:
directing a fan shape stream of air through a linear nozzle over one or more components in the chamber.

7. The method of claim 1 , wherein the pressurized jet of air includes hydrogen or oxygen radicals.

8. A method, comprising:
directing a first stream of gas comprising a solvent, through one or more nozzles, into a chamber in a lithography system when the lithography system is in maintenance mode;
extracting one or more particles by the first stream of gas that impinges on walls and one or more components of the chamber of the lithography system and dissolving organic material contamination by the solvent in the directed first stream of gas from surfaces of one or more components in the chamber of the lithography system;
drawing the first stream of gas that comprises the extracted one or more particles and the dissolved organic material contamination, through a first opening, out of the chamber of the lithography system;
directing the first stream of gas through a gas filter system coupled the chamber at the first opening;
collecting the one or more particles by a first filter of the gas filter system and collecting the dissolved organic material contamination by a second filter of the gas filter system to clean the first stream of gas;
continuously monitoring a number of particles and an amount of the organic material in the first stream of gas after the gas filter system;
recycling the cleaned first stream of gas into the chamber when the number of particles in the first stream of gas is below a first threshold and the amount of organic material in the first stream of gas is below a second threshold; and
maintaining a temperature of the chamber at a temperature close to a temperature of the lithography system during normal operation of the lithography system.

9. The method of claim 8 , wherein a first nozzle of the one or more nozzles is mounted above one of the one or more components, the method further comprising:
directing a pressurized jet of gas, at an angle of about 45 degrees with a vertical direction, out of the first nozzle; and
rotating an end of the first nozzle in an area in a plane perpendicular to the vertical direction.

10. The method of claim 8 , further comprising:
generating a second stream of gas by a first gas conducting system; and
combining the second stream of gas with a vaporized form of the solvent to produce the first stream of gas.

11. The method of claim 8 , further comprising:
drawing the first stream of gas, by a second gas conducting system coupled the chamber.

12. The method of claim 11 , further comprising:
automatically ending the maintenance mode when the number of particles in the first stream of gas continuously stays below the first threshold for a predetermined amount of time and the amount of organic material in the first stream of gas continuously stays below the second threshold for the predetermined amount of time.

13. The method of claim 8 , wherein the first stream of gas comprises a plurality of streams of gas that include first, second and more streams of gas, which are pressurized jets of gas each directed by separate nozzles at different angles.

14. A system, comprising:
a main controller;
a wafer table of an EUV lithography system comprising a chamber that comprises one or more wafer chucks and one or more wafer handling robots;
a gas source;
a first gas conducting system coupled to a first opening of the chamber of the wafer table;
a second gas conducting system coupled to a second opening of the chamber of the wafer table that comprises a particle counter-organic material detector coupled to the main controller; and
an exhaust controller coupled to the main controller, wherein
the main controller is configured to, during a maintenance mode:
direct a first stream of gas from the gas source, through the first opening, into the chamber of the wafer table, wherein the first stream of gas is configured to impinge on surfaces of walls and the one or more wafer chucks and the one or more wafer handling robots in the chamber of the wafer table to extract one or more particles from surfaces;
draw the first stream of gas and the extracted one or more particle, through the second opening, out of the chamber of the wafer table;
command the particle counter-organic material detector to continuously monitor a number of particles and an amount of organic material in the first stream of gas; and
command the exhaust controller to allow recycling of the first stream of gas to the chamber of the wafer table via the first gas conducting system when the number of particles is below a first threshold and the amount of organic material is below a second threshold.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Tu Shih-Yu
• Wang Shao-Hua
• Liu Yen-Hao
• Kuo Chueh-Chi
• Chen Li-Jui
• Liu Heng-Hsin

Classifications

• G03F7/70933

  Purge, e.g. exchanging fluid or gas to remove pollutants · CPC title

• G03F7/70925 Primary

  Cleaning, i.e. actively freeing apparatus from pollutants, e.g. using plasma cleaning · CPC title

• G03F7/7085

  Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load · CPC title

• G03F7/70916

  Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps · CPC title

• G03F7/70908 Primary

  Hygiene, e.g. preventing apparatus pollution, mitigating effect of pollution or removing pollutants from apparatus · CPC title