Projection exposure apparatus and method
AssigneeNikon Corporation
InventorsShigeru Yamasaki, Masahiko Okumura
Life of this patent
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Abstract
In a projection exposure apparatus and method in which a substrate is exposed with a projected image of a mask through a projection optical system, a table which is movable in a direction of an optical axis of the projection optical system in arranged at an image side of the projection optical system to hold the substrate. A tilt amount of the table is monitored, and position information of a mark on the table is detected, which changes in accordance with the tilt of the table. Information on the relationship between a displacement amount of the substrate and a plane perpendicular to the optical axis and the tilt angle of the substrate is obtained, based on the monitored tilt amount and the position information of the mark.
Claims32
A projection exposure apparatus which exposes a substrate with a projected image of a mask through a projection optical system, comprising:
- a mask table which is arranged at an object side of said projection optical system to hold said mask;
- a wafer table which is arranged at an image side of said projection optical system to hold said substrate, which is able to be tilted, and which is movable in a direction of an optical axis of said projection optical system, said wafer table being provided with a reflection surface thereon;
- an interferometer having a measurement axis with respect to said reflection surface to detect a first displacement amount of said substrate, in a predetermined direction perpendicular to said direction of the optical axis;
- a detection device independent from said interferometer, which detects a second displacement amount of said substrate, different from said first displacement amount, in said predetermined direction, said displacement amount being generated due to the tilt of said wafer table;
- and
- an adjusting device connected to one of said mask table and said wafer table to adjust relative positional relationship in said predetermined direction between an image plane of said projection optical system and said substrate, based on said second displacement amount.
A projection exposure apparatus which exposes a substrate with a projected image of a mask through a projection optical system, comprising:
- a table which is arranged at an image side of said projection optical system to hold said substrate, which is able to be tilted such that the substrate assumes a tilted position, and which is movable in a direction of an optical axis of said projection optical system;
- a tilt detection device which detects a tilt amount of said table;
- a mark detection system with a detection area disposed at the image side of said projection optical system to detect a mark on said table;
- and
- a detection device electrically connected to said tilt detection device and said mark detection system to detect information concerning relationship between a displacement amount of said substrate in a plane perpendicular to an optical axis of said projection optical system and a tilt angle of said substrate, based on mark position information detected by said mark detection system and a tilt amount of said table when said table is tilted, which change in accordance with the tilt of said table.
A projection exposure apparatus which exposes a substrate with a projected image of a mask through a projection optical system, comprising:
- a table which can be tilted, arranged at an image side of said projection optical system to hold said substrate;
- an interferometer having a measurement axis with respect to a reflection surface provided on said table;
- and
- an optical device arranged between said interferometer and said reflection surface to shift at least a portion of said measurement axis in a direction of an optical axis of said projection optical system.
An exposure method for exposing a substrate with a projected image of a mask through a projection optical system, comprising:
- detecting a first displacement amount of said substrate in a plane perpendicular to an optical axis of said projection optical system, by means of an interferometer having a measurement axis with respect to a reflection surface provided on a table which is able to be tilted while holding said substrate and which is movable in a direction of said optical axis;
- and
- detecting a second displacement amount of said substrate in said plane, which is generated due to the tilt of said table without change in measured value by said interferometer, said second displacement amount being different from said first displacement amount.
A projection exposure method for exposing a substrate with a projected image of a mask through a projection optical system, comprising:
- tilting a table which is able to be tilted while holding said substrate, and which is movable in a direction of an optical axis of said projection optical system;
- monitoring a tilt amount of said table;
- detecting position information of a mark on said table, which changes in accordance with the tilt of said table;
- and
- obtaining information on relationship between a displacement amount of said substrate in a plane perpendicular to said optical axis and a tilt angle of said substrate, based on the monitored tilt amount and said position information of the mark.
A projection exposure method for exposing a substrate held on a table which is able to be tilted, with a projected image of a mask through a projection optical system, comprising:
- measuring a position of said substrate by means of an interferometer having a measurement axis with respect to a reflection surface provided on said table;
- and
- shifting at least a portion of said measurement axis between said interferometer and said reflection surface in a direction of an optical axis of said projection optical system, in accordance with a tilt of said table.
A method of manufacturing a device, wherein a substrate used in forming the device is exposed with a projected image of a mask through a projection optical system, said method comprising:
- detecting a first displacement amount of said substrate in a plane perpendicular to an optical axis of said projection optical system, by means of an interferometer having a measurement axis with respect to a reflection surface provided on a table which is able to be tilted while holding said substrate and moveable in the direction of said optical axis;
- detecting a second displacement amount of said substrate in said plane, which is generated due to the tilt of said table without change in measured value by said interferometer, said second displacement amount being different from said first displacement amount;
- and
- adjusting positional relationship of said mask and said substrate with respect to a direction perpendicular to said optical axis of said projection optical system based on said first and second displacement amounts.
Dependencies are inferred from the claim text.