Metrology Apparatus, Method of Measuring a Structure and Lithographic Apparatus
AssigneeASML Netherlands B.V.
InventorsAlessandro POLO, Simon Gijsbert Josephus Mathijssen
Life of this patent
Estimating the term…
Abstract
Disclosed is a metrology apparatus and method for measuring a structure formed on a substrate by a lithographic process. The metrology apparatus comprises an illumination system operable to provide measurement radiation comprising a plurality of wavelengths; and a hyperspectral imager operable to obtain a hyperspectral representation of a measurement scene comprising the structure, or a part thereof, from scattered measurement radiation subsequent to the measurement radiation being scattered by the structure.
Claims21
1-26. (canceled)
A metrology apparatus for measuring a structure formed on a substrate by a lithographic process, said metrology apparatus comprising:
- an illumination system operable to provide measurement radiation comprising a plurality of wavelengths;
- and
- a hyperspectral imager operable to obtain a hyperspectral representation of a measurement scene comprising the structure, or a part thereof, from scattered measurement radiation subsequent to said measurement radiation being scattered by said structure.
An alignment sensor comprising a metrology apparatus for measuring an alignment structure formed on a substrate by a lithographic process, said metrology apparatus comprising:
- an illumination system operable to provide measurement radiation comprising a plurality of wavelengths;
- and
- a hyperspectral imager operable to obtain a hyperspectral representation of a measurement scene comprising the structure, or a part thereof, from scattered measurement radiation subsequent to said measurement radiation being scattered by said structure.
A method of measuring a structure formed on a substrate by a lithographic process comprising:
- illuminating the structure with measurement radiation comprising a plurality of wavelengths, such that the measurement radiation is scattered by the structure;
- spatially modulating the scattered measurement radiation with a coded pattern to obtain coded measurement radiation;
- spectrally dispersing the coded measurement radiation to obtain a two-dimensional coded spatio-spectral projection;
- sensing the two-dimensional coded spatio-spectral projection;
- and
- estimating a hyperspectral representation of the structure from the two-dimensional coded spatio-spectral projection and knowledge of the coded pattern.
The lithography apparatus, arranged to transfer a pattern from a patterning device onto a substrate, comprising an alignment sensor with a metrology apparatus for measuring an alignment structure formed on the substrate, said metrology apparatus comprising:
- an illumination system operable to provide measurement radiation comprising a plurality of wavelengths;
- and
- a hyperspectral imager operable to obtain a hyperspectral representation of a measurement scene comprising the structure, or a part thereof, from scattered measurement radiation subsequent to said measurement radiation being scattered by said structure.
Dependencies are inferred from the claim text.