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AssigneeApplied Materials, Inc.
InventorsAvner Karpol, Silviu Reinhorn, Emanuel Elysaf, Shimon Yalov, Boaz Kenan
Estimating the term…
A method and apparatus for reducing speckle during inspection of articles used in the manufacture of semiconductor devices, including wafers, masks, photomasks, and reticles. The coherence of a light beam output by a coherent light source, such as a pulsed laser, is reduced by disposing elements in a light path. Examples of such elements include optical fiber bundles; optical light guides; optical gratings; an integrating sphere; and an acousto-optic modulator. These various elements may be combined as desired, such that light beams output by the element combinations have optical path length differences that are greater than a coherence length of the light beam output by the coherent light source.
In the inspection of a patterned article used in the manufacture of semiconductor devices, a method of reducing speckle, said method comprising:
In the inspection of a patterned article used in the manufacture of semiconductor devices, a method of reducing speckle, said method comprising:
In the inspection of a patterned article used in the manufacture of semiconductor devices, a method of reducing speckle, said method comprising:
In the inspection of a patterned article used in the manufacture of semiconductor devices, a method of reducing speckle, said method comprising:
In the inspection of a patterned article used in the manufacture of semiconductor devices, a method of reducing speckle, said method comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Backward citations are indexed for grants only.
Workpiece metrology: monitoring the printed patterns
Scattering, i.e. diffuse reflection: diffraction
Characterised by the material or shape of the object to be examined: semiconductor wafers
Characterised by the material or shape of the object to be examined: inspecting patterns on the surface of objects
Term end not estimated
1. Field of the Invention
The present invention relates to inspection of articles, and in particular, to inspection of articles related to the manufacture of semiconductor devices. More specifically, the invention relates to the inspection of articles used in photolithography during the manufacture of semiconductor devices.
2. Description of the Related Art
The above features and advantages of the present invention will become more apparent when referring to the following detailed description of preferred embodiments thereof with reference to the attached drawings in which like reference numbers represent corresponding parts throughout, in which:
FIGS. 1A and 1B show examples of inspection devices for use in accordance with the present invention;
FIGS. 2A and 2B show a first embodiment of the present invention, and a variant thereof;
In the following description of preferred embodiments of the present invention, reference is made to the accompanying drawings, which form a part thereof, and which show by way of illustration specific embodiments of the invention. It is to be understood by those of working skill in this technological field that other embodiments may be utilized, and structural changes may be made without departing from the scope of the present invention.
FIG. 1A shows an exemplary inspection device for use in accordance with the present invention. The inspection device shown in FIG. 1A is operating in a reflective mode. However, it is to be understood that inspection devices operating in a transmissive mode, or in both a transmissive and a reflective mode, are within the contemplation of the invention. At least for the transmissive mode of operation, a beam homogenizer should be employed prior to the beam's entering a coherence reduction/speckle reduction apparatus.
In FIG. 1A, an article 1 to be inspected, such as a wafer, a mask, a photomask, or a reticle, is positioned on an x-y stage 2, which moves the article 1 in two directions. The inspection device includes a coherent light source 4, preferably a laser, located on one side of the article 1. The light source 4 may be a continuous wave laser, or may be a pulsed laser, emitting low wavelength laser beams in the UV or deep UV region. The beams emitted by the light source 4 are directed via an optical system 6, a beam splitter 8 and an objective lens 10 onto the surface of the article 1. It should be noted that other means of directing the beams onto the article 1, including other optical paths defined by suitable structure, also may be used.