Measurement apparatus, exposure apparatus, and device fabrication method
AssigneeCanon Kabushiki Kaisha
InventorRyo Sasaki
Life of this patent
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Abstract
The present invention provides a measurement apparatus which measures a height of a test surface, the apparatus including an image sensing device including a plurality of detection units configured to detect interfering light formed by measurement light from the test surface and reference light from a reference surface, and an optical system configured to guide the measurement light and the reference light to the plurality of detection units, wherein the reference surface is placed such that differences are generated among optical path differences between measurement light beams and reference light beams which enter the plurality of detection units, respectively.
Claims5
A measurement apparatus which measures a height of a test surface, the apparatus comprising:
- an image sensing device including a plurality of detection units configured to detect interfering light formed by measurement light from the test surface and reference light from a reference surface;
- and
- an optical system configured to guide the measurement light and the reference light to said plurality of detection units,
- wherein the reference surface is placed such that differences are generated among optical path differences between measurement light beams and reference light beams which enter said plurality of detection units, respectively, and
- said plurality of detection units detect the interfering light by moving a relative position between the test surface and a measurement unit including said image sensing device and said optical system so that measurement light beams reflected at a plurality of measurement points on the test surface, and reference light beams reflected at a plurality of reference points on the reference surface enter said plurality of detection units, respectively.
A device fabrication method comprising steps of:
- exposing a substrate using an exposure apparatus;
- and
- performing a development process for the substrate exposed,
- wherein the exposure apparatus includes:
- a projection optical system configured to project a pattern of a reticle onto the substrate;
- a measurement apparatus configured to measure a height of the substrate to obtain a surface shape of the substrate;
- and
- a stage configured to adjust a position of the substrate based on the surface shape of the substrate measured by said measurement apparatus,
- wherein the measurement apparatus includes:
- an image sensing device including a plurality of detection units configured to detect interfering light formed by measurement light from the substrate and reference light from a reference surface;
- and
- an optical system configured to guide the measurement light and the reference light to said plurality of detection units,
- wherein the reference surface is placed such that difference are generated among optical path differences between measurement light beams and reference light beams which enter said plurality of detection units, respectively, and
- said plurality of detection units detect the interfering light by moving a relative position between the substrate and a measurement unit including said image sensing device and said optical system so that measurement light beams reflected at a plurality of measurement points on the substrate, and reference light beams reflected at a plurality of reference points on the reference surface enter said plurality of detection units, respectively.
Dependencies are inferred from the claim text.