Projection exposure method and projection exposure apparatus

Patent metadata

Field	Value
Publication number	US-9933710-B2
Application number	US-201715470007-A
Country	US
Kind code	B2
Filing date	Mar 27, 2017
Priority date	Apr 5, 2016
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

A projection exposure method for exposing a radiation-sensitive substrate with at least one image of a pattern of a mask in a projection exposure apparatus includes using an anamorphic projection lens

First claim

What is claimed is:

1. A method of using a projection exposure apparatus comprising an illumination system and an anamorphic projection lens, the method comprising:
using the illumination system to illuminate an illumination region of a mask which comprises a pattern, the mask being located in a region of an object plane of the anamorphic projection lens;
using the anamorphic projection lens to project an illuminated part of the pattern of the mask onto a radiation-sensitive material located in an image plane of the anamorphic projection lens;
synchronously moving the mask and the radiation-sensitive material in a respective scanning direction during a scan operation;
rotating the mask by a first angle about a first axis oriented perpendicular to the object plane of the anamorphic lens; and
rotating the radiation-sensitive material by a second angle about a second oriented perpendicular to the image plane of the anamorphic lens,
wherein the rotation of the mask and the rotation of the radiation-sensitive material are coordinated with one another so that:
for a first aberration caused by the rotation of the mask, a profile over the image field is set; and
for a second image aberration caused by the rotation of the mask, a profile over the image field is compensated for by the rotation of the sub radiation-sensitive material to a greater extent than the profile of the first image aberration over the image field.

2. The method of claim 1 , comprising synchronously rotating the mask and the radiation-sensitive material about the assigned rotation axes during the scan operation so that the rotation of the mask and the rotation of the radiation-sensitive material, in a time interval between the beginning and end of a scan operation proceeding in one direction, are effected synchronously with variation of the first and second rotation angles according to a predefinable movement profile.

3. The method of claim 2 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a ratio of the first and second imaging scales.

4. The method of claim 2 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a reciprocal of a ratio of the first and second imaging scales.

5. The method of claim 1 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a ratio of the first and second imaging scales.

6. The method of claim 1 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a reciprocal of a ratio of the first and second imaging scales.

7. The method of claim 1 , further comprising:
determining a movement profile for rotating the mask by the first angle and for rotation the radiation-sensitive material by the second angle; and
synchronously rotating the mask by the first angle and the radiation-sensitive material by the second angle rotation axes during the scan operation according to the movement profile.

8. An apparatus configured to expose a radiation-sensitive material with an image of a pattern of a mask, the apparatus comprising:
an illumination system configured to generate an illumination radiation directed onto the mask;
an anamorphic projection lens configured to generate an image of the pattern in the region of an image plane of the projection lens;
a mask holding unit configured to hold the mask between the illumination system and the projection lens so that the pattern is arranged in a region of an object plane of the anamorphic projection lens and so that the pattern is movable in a scanning direction perpendicular to a reference axis of the anamorphic projection lens;
a substrate holding unit configured to hold the radiation-sensitive material so that the radiation-sensitive material is in a region of the image plane of the anamorphic projection lens, and so that the radiation-sensitive material is synchronously movable with the mask perpendicular to the reference axis of the projection lens; and
a control unit,
wherein:
the image plane is optically conjugate to the object plane;
the mask holding unit comprises a first rotation unit configured to controllably rotate the mask about a first rotation axis running orthogonally with respect to the object plane;
the substrate holding unit comprises a second rotation unit configured to controllably rotate the radiation-sensitive material about a second rotation axis running orthogonally with respect to the image plane;
the control unit is configured to rotate the mask holding unit and the substrate holding unit in a manner coordinated with each other so that:
for a first image aberration caused by the rotation of the mask, a profile over the image field is set; and
for a second image aberration caused by the rotation of the mask, a profile over the image field is compensated for by the rotation of the radiation-sensitive material to a greater extent than the profile of the first image aberration over the image field; and

the apparatus is a projection exposure apparatus.

9. The apparatus of claim 8 , wherein the first and second rotation units are configured so that a rotation of the mask and of the radiation-sensitive material, in a time interval between the beginning and end of a scan operation proceeding in one direction, is controllable according to a predefinable movement profile.

10. The apparatus of claim 9 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a ratio of the first and second imaging scales.

11. The apparatus of claim 9 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is different from the first imaging scale; and
the first and second rotation angles are in a ratio to one another which corresponds to a reciprocal of a ratio of the first and second imaging scales.

12. The apparatus of claim 8 , wherein:
the anamorphic projection lens has a first imaging scale in a first direction;
the anamorphic projection lens has a second imaging scale in a second direction perpendicular to the first direction;
the second imaging scale is diffe

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Andre Stephan
• Golde Daniel
• Gruner Toralf
• Ruoff Johannes

Classifications

• G03F7/70775 Primary

  Position control, e.g. interferometers or encoders for determining the stage position · CPC title

• G03F7/70525

  Controlling normal operating mode, e.g. matching different apparatus, remote control or prediction of failure · CPC title

• G03F9/70

  for microlithography (measuring printed patterns for monitoring overlay G03F7/70633 or focus G03F7/70641; projection system adjustment G03F7/70258; position control G03F7/70775) · CPC title

• G03F7/201

  characterised by an oblique exposure; characterised by the use of plural sources; characterised by the rotation of the optical device; characterised by a relative movement of the optical device, the light source, the sensitive system or the mask · CPC title

• G03F7/2004

  characterised by the use of a particular light source, e.g. fluorescent lamps or deep UV light · CPC title