Profile measuring apparatus, method for measuring profile, and method for manufacturing product
AssigneeNikon Corporation
InventorTomoaki YAMADA
Life of this patent
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Abstract
There is provided a profile measuring apparatus which measures a profile of an object, including an imaging element; an image formation optical system including an objective lens; a measuring direction changing unit which is configured to change inclination of a surface of the object with respect to the objective lens based on information of the inclination of the surface of the object so that a light flux enters the objective lens with an aperture angle not less than a predetermined degree; and a measuring unit which is configured to measure the profile of the object based on the image, of the object on which the pattern is projected, obtained by the imaging element.
Claims13
A profile measuring apparatus which measures a profile of an object, comprising;
- an imaging element which is configured to take an image of the object on which a pattern is projected;
- an image formation optical system which is arranged to form an image of the pattern, projected on the object, on the imaging element and which includes an objective lens that condenses a light flux from the object on which the pattern is projected;
- a measuring direction changing unit which is configured to change inclination of a surface of the object with respect to the objective lens based on information of the inclination of the surface of the object so that a light flux from a point of the object, reaching the imaging element through the objective lens, enters the objective lens with an aperture angle not less than a predetermined degree;
- and,
- a measuring unit which is connected to the imaging element and measures the profile of the object based on the image, of the object on which the pattern is projected, obtained by the imaging element.
A profile measuring apparatus which measures a profile of an object, comprising:
- a projection optical system which is configured to project an image of a pattern onto the object;
- an imaging unit which is arranged to be connected optically with the projection optical system and which is configured to take a first image that is an image of the object on which the image of the pattern is projected;
- an illumination optical system which is arranged to be connected optically with the imaging unit and which is configured to irradiate the object with a parallel light flux from a predetermined direction;
- a pupil image formation unit which is arranged to be connected optically with the projection optical system and which is configured to form a pupil image of the object in a pupil of an optical imaging system provided in the imaging unit;
- a pupil image taking unit which is arranged to be connected optically with the projection optical system and which is configured to take, as a second image, the pupil image of the object formed by the pupil image formation unit;
- an inclination measuring unit which is connected to the pupil image taking unit and which is configured to measure inclination of a surface of the object based on the second image taken by the pupil image taking unit;
- and
- a measuring unit which is connected to the imaging element and which is configured to measure the profile of the object by a shape from focus method utilizing the first image taken from the imaging unit.
A method for measuring a profile of an object by projecting a pattern onto a surface of the object, the method comprising:
- acquiring inclination information of the surface of the object;
- changing inclination of the surface of the object with respect to an objective lens of an image formation optical system based on the inclination information of the surface of the object so that under a condition that a light flux of the pattern projected on a position of the object entering the objective lens, and reaching an imaging element through the objective lens has an aperture angle with a predetermined angular width;
- and
- measuring the profile of the object by acquiring degree of focus for an image of the object at each of the different points obtained by the image formation optical system.
Dependencies are inferred from the claim text.