Lithographic apparatus and device manufacturing method

Patent metadata

Field	Value
Publication number	US-9939740-B2
Application number	US-201515116794-A
Country	US
Kind code	B2
Filing date	Jan 20, 2015
Priority date	Feb 20, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A lithographic apparatus including a barrier system and a device manufacturing method using such a lithographic apparatus. The barrier system is used to maintain a protected volume of gas within a barrier. The protected volume may be maintained when different components of the lithographic apparatus move relative to each other. The barrier system may be used in different locations within the lithographic apparatus. The geometry of the barrier affects how efficiently the protected volume is maintained, especially at high speeds. The geometry reduces the amount of ambient gas entering the protected volume from outside the barrier.

First claim

The invention claimed is:

1. A lithographic apparatus comprising a first component and a second component that are configured to undergo relative movement with respect to one another in a scanning direction and/or a stepping direction substantially perpendicular to the scanning direction, wherein:
the first component has a first surface;
the second component has a second surface;
wherein the first surface and the second surface face each other;
at least the first surface and/or the second surface accommodates a barrier system; and
the barrier system is configured to provide a barrier operative to reduce or prevent an inflow of ambient gas into a protected volume of gas between the first surface and the second surface; and
the barrier system comprises at least one selected from:
a wall forming the barrier, the wall enclosing part of the protected volume adjacent the first surface and/or second surface; and/or
at least one opening adapted for a flow of barrier gas therefrom for establishing a gas curtain as the barrier, the gas curtain enclosing part of the protected volume adjacent the first surface and/or second surface;

the barrier has a geometry in a plane in which the scanning direction and the stepping direction lie, and the barrier is operative to guide a flow of ambient gas around the protected volume, the flow of ambient gas being induced by the relative movement of the first component and the second component;
the geometry has a first corner and a second corner;
the first corner serves as a leading edge of the barrier and the second corner serves as a trailing edge of the barrier when the first component and the second component move relative to one another in a specific direction being the scanning direction or the stepping direction; and
the first corner serves as the trailing edge of the barrier and the second corner serves as the leading edge of the barrier when the first component and the second component move relative to one another in a further direction opposite to the specific direction,
wherein (i) the first component or the second component comprises a movable table, and the other of first component or the second component comprises a reference frame, or (ii) the first component or the second component comprises a structure at a top end of a projection system configured to project a projection beam onto a substrate.

2. The lithographic apparatus of claim 1 , wherein at the first surface and/or the second surface, an imaginary line in a first direction is defined, the imaginary line passing through the first corner and the second corner.

3. The lithographic apparatus of claim 2 , wherein the geometry is symmetrical about the first direction.

4. The lithographic apparatus of claim 1 , wherein the barrier system comprises the at least one opening adapted for a flow of barrier gas therefrom for establishing a gas curtain enclosing part of the protected volume adjacent the first surface and/or second surface and wherein an opening of the at least one opening is an inner opening providing a turbulent flow of barrier gas, and/or wherein an opening of the at least one opening is an outer opening providing a laminar flow of barrier gas.

5. The lithographic apparatus of claim 1 , wherein a radiation beam passes through the protected volume and the radiation beam is a radiation beam directed to a sensor.

6. The lithographic apparatus of claim 5 , wherein the first and/or second component has/have at least one target thereon for detection by the sensor.

7. The lithographic apparatus of claim 5 , wherein the sensor is an alignment sensor configured to measure alignment of one object relative to another.

8. The lithographic apparatus of claim 5 , wherein the first component or the second component comprises the movable table, and the other of first component or the second component comprises a reference frame.

9. The lithographic apparatus of claim 7 , wherein the protected volume is in contact with the sensor.

10. The lithographic apparatus of claim 5 , wherein the sensor is a level sensor configured to measure the topography of a surface.

11. The lithographic apparatus of claim 1 , comprising the structure at a top end of a projection system configured to project a projection beam onto a substrate, and the first component or the second component comprises the structure.

12. The lithographic apparatus of claim 11 , comprising a patterning device table, and the other of the first component or second component comprises the patterning device table.

13. A device manufacturing method comprising projecting a projection beam onto a substrate positioned on a substrate table in an apparatus and/or using a beam of radiation to measure a property of the apparatus, wherein the projection beam and/or the beam of radiation passes through a protected volume of gas protected by a barrier system configured to provide a barrier, the barrier being operative to reduce or prevent an inflow of ambient gas into the protected volume of gas between a first surface and a second surface of the apparatus, the apparatus comprising a first component having the first surface and further comprising a second component having the second surface, the first component and the second component being configured to undergo relative movement with respect to one another in a scanning direction and/or a stepping direction substantially perpendicular to the scanning direction,
wherein at least the first surface and/or the second surface accommodates the barrier system;
wherein the barrier is in the form of a wall enclosing part of the protected volume adjacent the first surface and/or second surface and/or the barrier is in the form of a flow of barrier gas establishing a gas curtain enclosing part of the protected volume adjacent the first surface and/or second surface;
wherein the barrier has a geometry in a plane in which the scanning direction and the stepping direction lie, and the barrier is operative to guide a flow of the ambient gas around the protected volume, the flow of the ambient gas being induced by the relative movement of the first component and the second component;
the geometry has a first corner and a second corner;
the first corner serves as a leading edge of the barrier and the second corner serves as a trailing edge of the barrier when the first component and the second component move relative to one another in a specific direction being the scanning direction or the stepping direction; and
the first corner serves as the trailing edge of the barrier and the second corner serves as the leading edge of the barrier when the first component and the second component move relative to one another in a further direction opposite to the specific direction,
wherein (i) the first component or the second component comprises a movable table, and the other of first component or the second component comprises a reference frame, or (ii) the first component or the second component comprises a structure at a top end of a projection system configured to project a projection beam onto a substrate.

14. The method of claim 13 , wherein at the first surface and/or second surface, an imaginary line in a first direction is defined, the imaginary line passing through the first corner and the second corner.

15. The method of claim 13 , wherein the radiation beam passes through the protected volume and the radiation beam is a radiation beam directed to a sensor.

16. The method of claim 15 , wherein the first and/or second component has/have at least one target thereon for detection by the sensor.

17. The m

Assignees

• Asml Netherlands Bv

Inventors

• Nakiboglu Günes
• Van Baren Martijn
• Van Boxtel Frank Johannes Jacobus
• Cuypers Koen
• Gosen Jeroen Gerard
• Van Bokhoven Laurentius Johannes Adrianus

Classifications

• G03F7/70908

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

• G03F7/70858 Primary

  Environment aspects, e.g. pressure of beam-path gas, temperature (pollution aspects G03F7/70916) · CPC title

• G03F7/70716

  Stages · CPC title

• G03F7/70358 Primary

  Scanning exposure, i.e. relative movement of patterned beam and workpiece during imaging · CPC title

• G03F7/704

  Scanned exposure beam, e.g. raster-, rotary- and vector scanning (mask projection exposure involving relative movement of patterned beam and workpiece during imaging G03F7/70358) · CPC title