Detection apparatus, detection method, exposure apparatus and article manufacturing method
A detection apparatus including a plurality of detection systems arranged spaced apart from each other so as to detect, of a plurality of marks provided on an object held by a stage, marks different from each other, and a processing unit configured to perform a first process of obtaining a first detection value by detecting the plurality of marks by one or more detection systems in a first state in which the stage is arranged at a first rotation angle, and a second process of obtaining a second detection value by detecting the plurality of marks by two or more detection systems in a second state in which the stage is arranged at a second rotation angle, and obtain a difference between the first detection value and the second detection value for each of the plurality of marks.
1. A detection apparatus for detecting a plurality of marks provided on an object, the detection apparatus comprising:
a stage configured to be rotatable while holding the object;
a plurality of detection systems arranged spaced apart from each other so as to detect, of the plurality of marks provided on the object held by the stage, marks different from each other; and
a processing unit configured to perform a first process of obtaining a first detection value by detecting the plurality of marks by one or more detection systems of the plurality of detection systems in a first state in which the stage is arranged at a first rotation angle, and a second process of obtaining a second detection value by detecting the plurality of marks by two or more detection systems of the plurality of detection systems in a second state in which the stage is arranged at a second rotation angle different from the first rotation angle, and obtain a difference between the first detection value and the second detection value for each of the plurality of marks,
wherein the second state is a state in which the stage is rotated with, as a center, one axis in a plane parallel to a holding surface of the stage for holding the object.
2. The apparatus according to claim 1 , wherein:
for a first object, the processing unit obtains the difference by performing the first process and the second process, and
for a second object processed after the first object, the processing unit performs a third process of obtaining a third detection value by detecting a plurality of marks provided on the second object by two or more detection systems of the plurality of detection systems in a third state in which the stage is arranged at a third rotation angle different from the second rotation angle.
3. The apparatus according to claim 2 , wherein the second state and the third state are different in at least one of a rotation direction or a rotation amount of the stage.
4. The apparatus according to claim 3 , wherein the processing unit obtains a correction value by correcting the third detection value using the difference, a rotation difference between the second rotation angle and the third rotation angle, and a coefficient representing a relationship between a rotation angle of the stage and an error amount included in the detection value of the mark.
5. The apparatus according to claim 4 , wherein the processing unit obtains the correction value by subtracting the difference and a product of the rotation difference and the coefficient from the third detection value.
6. The apparatus according to claim 4 , wherein the processing unit obtains the coefficient in advance based on detection values obtained by detecting a reference mark provided on the stage by the plurality of detection systems while changing the rotation angle of the stage.
7. The apparatus according to claim 1 , wherein the processing unit updates the difference by performing the first process and the second process in accordance with a change of a lot which is a unit to process the object.
8. The apparatus according to claim 1 , wherein the processing unit updates the difference by performing the first process and the second process in accordance with a change of a layout of the plurality of marks provided on the object.
9. The apparatus according to claim 1 , wherein the processing unit updates the difference by performing the first process and the second process in accordance with an elapse of a predetermined time.
10. A detection method of detecting a plurality of marks by using a detection unit that includes a stage configured to be rotatable while holding an object, and a plurality of detection systems arranged spaced apart from each other so as to detect, of the plurality of marks provided on the object held by the stage, marks different from each other, the method comprising:
obtaining a first detection value by detecting the plurality of marks by one or more detection systems of the plurality of detection systems in a first state in which the stage is arranged at a first rotation angle;
obtaining a second detection value by detecting the plurality of marks by two or more detection systems of the plurality of detection systems in a second state in which the stage is arranged at a second rotation angle different from the first rotation angle; and
obtaining a difference between the first detection value and the second detection value,
wherein the second state is a state in which the stage is rotated with, as a center, one axis in a plane parallel to a holding surface of the stage for holding the object.
11. An exposure apparatus for exposing a substrate, the exposure apparatus comprising:
a detection apparatus configured to detect a plurality of marks provided on the substrate serving as an object, wherein the detection apparatus includes:
a stage configured to be rotatable while holding the substrate;
a plurality of detection systems arranged spaced apart from each other so as to detect, of the plurality of marks provided on the substrate held by the stage, marks different from each other; and
a processing unit configured to perform a first process of obtaining a first detection value by detecting the plurality of marks by one or more detection systems of the plurality of detection systems in a first state in which the stage is arranged at a first rotation angle, and a second process of obtaining a second detection value by detecting the plurality of marks by two or more detection systems of the plurality of detection systems in a second state in which the stage is arranged at a second rotation angle different from the first rotation angle, and obtain a difference between the first detection value and the second detection value for each of the plurality of marks,
wherein the second state is a state in which the stage is rotated with, as a center, one axis in a plane parallel to a holding surface of the stage for holding the object.
12. An article manufacturing method comprising:
exposing a substrate using an exposure apparatus defined in claim 11 ;
developing the exposed substrate; and
manufacturing an article from the developed substrate.