Lithographic Apparatus and Device Manufacturing Method with Radiation Beam Inspection

• US 20090219500A1
• Filed: 05/07/2009
• Published: 09/03/2009
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: DAVIS, Todd J., PAXTON, Theodore Allen, HIAR, Todd David, TEL, Wim Tjibbo, VAN DER LAAN, Hans, OWEN, Cassandra May
• Granted Patent: US 8,937,705 B2
• Time in Patent Office: Days
• US Class Current: 355/67
• CPC Class Codes: G03F 7/70375 Multiphoton lithography or multiphoton photopolymerization; Imaging systems comprising means for converting one type of radiation into another type of radiation
• CPC Class Codes: G03F 7/70666 Aerial image, i.e. measuring the image of the patterned exposure light at the image plane of the projection system

Abstract

A lithographic apparatus can include the following devices: a patterning system, a projection system, and a radiation beam inspection device. The patterning system can be configured to provide a patterned radiation beam. The projection system can be configured to project the patterned radiation beam onto a target portion of a substrate. Further, the radiation beam inspection device can be configured to inspect at least a part of the patterned radiation beam. In a substrate exposure position, the projection system is configured to expose a pattern of radiation on the substrate using the patterned radiation beam and the radiation beam device is configured to move the reflecting device away from a light path of the patterned radiation beam. In a radiation beam inspection position, the radiation beam inspection device is configured to move the reflecting device into the light path of the patterned radiation beam.

Claims

1. A lithographic apparatus, comprising:

a patterning system configured to provide a patterned radiation beam;

a projection system configured to project the patterned radiation beam onto a target portion of a substrate; and

a radiation beam inspection device comprising a sensor and a reflecting device and configured to inspect at least a part of the patterned radiation beam,

wherein in a substrate exposure position, the projection system is configured to expose a pattern of radiation on the substrate using the patterned radiation beam and the radiation beam inspection device is configured to move the reflecting device away from a light path of the patterned radiation beam, and

wherein in a radiation beam inspection position, the radiation beam inspection device is configured to move the reflecting device into the light path of the patterned radiation beam, thereby directing the patterned radiation beam towards the sensor.

2. The lithographic apparatus of claim 1, wherein the reflecting device comprises a planar reflector configured to be rotatable between a first position and a second position, the first position corresponding to bypassing the patterned radiation beam during the exposure of the pattern of radiation on the substrate and second group corresponding to interfering with the patterned radiation beam during the radiation beam inspection.

3. The lithographic apparatus of claim 2, wherein said required pattern to be exposed on the substrate is a pattern corresponding to pattern features required to be formed on the substrate, modified according to a characterization of differences resulting from variations in conditions of processing the substrate, between the pattern of radiation exposed on the substrate, and the pattern features formed on the substrate.

4. The lithographic apparatus of claim 2, wherein:

said required pattern data store is configured to store data corresponding to at least a part of a pattern of features required to be formed on the substrate and a characterization of differences, resulting from variations in conditions of processing the substrate, between the pattern of radiation exposed on the substrate and the pattern features formed on the substrate; and

the controller device is configured to determine the pattern required to be exposed on the substrate from the data stored in said required pattern data store.

5. The lithographic apparatus of claim 1, wherein:

the patterning system comprises an array of individually controllable elements; and

said at least one modification to the operation of the lithographic apparatus comprises at least one change to the pattern set by the array of individually controllable elements.

6. The lithographic apparatus of claim 5, wherein said at least one change to the pattern set by the array of the individually controllable elements comprises at least one of an addition of a pattern feature, a removal of a pattern feature, and a re-sizing of a pattern feature.

7. The lithographic apparatus of claim 5, wherein:

said array of individually controllable elements is constructed such that the intensity of portions of the patterned radiation beam is set to at least three different levels; and

said at least one change to the pattern set by the array of individually controllable elements comprises adjusting an intensity of the patterned radiation beam in at least one portion of the pattern of radiation.

8. The lithographic apparatus of claim 5, further comprising a corrected pattern data store configured to store pattern data, corresponding to said required pattern to be exposed on the substrate, modified according to the at least one change to the pattern set by the array of individually controllable elements determined by the controller device and the array of individually controllable elements is set according to the pattern data in said corrected pattern data store.

9. The lithographic apparatus of claim 1, further comprising:

a required pattern data store configured to store data corresponding to at least a part of a required pattern to be exposed on the substrate; and

a controller device configured to determine the difference between the pattern detected by the radiation beam inspection device with the required pattern and to determine at least one modification to an operation of the lithographic apparatus necessary in order to minimize said difference.

10. The lithographic apparatus of claim 9, wherein:

the controller device is configured to modify an operation of the lithographic apparatus according to the at least one modification determined by the controller device while the lithographic apparatus is in the radiation beam inspection position; and

the controller device is configured to determine remaining differences between the pattern detected by the radiation beam inspection device and the required pattern and to determine further modifications to the operation of the lithographic apparatus to minimize said difference.

11. The lithographic apparatus of claim 9, wherein said at least one modification to the operation of the lithographic apparatus comprises at least one of an alteration of an intensity of the radiation beam provided by the patterning system, an alteration of the conditioning of the radiation beam by the patterning system, and an alteration of one or more settings of the projection system.

12. The lithographic apparatus of claim 11, further comprising:

a system settings data store configured to store data corresponding to said alteration of at least one of the intensity of the radiation beam provided by the patterning system, the conditioning of the radiation beam by the patterning system, and one or more settings of the projection system; and

a system controller configured to control the lithographic apparatus, in the substrate exposure position, using the data stored in the system settings data store.

13. A method of optimizing operation of a lithographic apparatus for formation of a device on a substrate, the method comprising:

moving a reflecting device into an exposure light path to direct a patterned beam of radiation onto a radiation beam inspection device, wherein the radiation beam inspection device is configured to inspect the pattern of radiation that would be exposed on the substrate that is along the exposure light path;

determining at least one modification to an operation of the lithographic apparatus to minimize a difference between a required pattern to be exposed on the substrate and the pattern determined by the radiation beam inspection device; and

projecting a modified patterned radiation beam onto the substrate, after moving the reflecting device out of the exposure light path, with the at least one modification used to produce the modified patterned radiation beam.

14. The method of claim 13, further comprising:

storing data corresponding to at least part of a required pattern to be exposed on the substrate;

determining the difference between the pattern detected by the radiation beam inspection device and the required pattern; and

determining at least one modification to an operation of the lithographic apparatus to minimize the difference.

15. The method of claim 14, wherein the determining at least one modification comprises modifying an operation of the lithographic apparatus according to the at least one modification determined by a controller device while the lithographic apparatus is in the radiation beam inspection position.

16. The method of claim 15, wherein the modifying the operation of the lithographic apparatus comprises:

determining a remaining difference between the pattern detected by the radiation beam inspection device and the required pattern; and

determining further modification to the operation of the lithographic apparatus to minimize the difference.

17. The method of claim 14, wherein the determining at least one modification to the operation of the lithographic apparatus comprises:

determining at least one of an alteration of an intensity of the radiation beam provided by an illumination system in the lithographic apparatus, an alteration of the conditioning of the radiation beam by the illumination system, and an alteration of one or more settings of the projection system.

18. The method of claim 17, further comprising:

storing data corresponding to the alteration of at least one of the intensity of the radiation beam provided by the illumination system, the conditioning of the radiation beam by the illumination system, and one or more settings of a projection system in the lithographic apparatus; and

controlling the lithographic apparatus, in the substrate exposure position, using the stored data.

19. The method of claim 14, wherein:

the storing data corresponding to at least part of the required pattern comprises storing data corresponding to pattern features required to be formed on the substrate; and

the pattern features are modified according to a characterization of differences from variations in conditions of processing the substrate, between the pattern of radiation exposed on the substrate, and the pattern features formed on the substrate.

20. The method of claim 14, wherein the storing data corresponding to at least part of the required pattern comprises storing data corresponding to at least a part of a pattern of features required to be formed on the substrate and a characterization of differences, resulting from variations in conditions of processing the substrate, between the pattern of radiation exposed on the substrate and the pattern features formed on the substrate.