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AssigneeNumerical Technologies, Inc.
InventorsYao-Ting Wang, Christophe Pierrat, Fang-Cheng Chang
Estimating the term…
One embodiment of the invention provides a system that facilitates exposing a wafer through at least two masks during an integrated circuit manufacturing process. The system includes a radiation source and two or more illuminators. Each of these illuminators receives radiation from the radiation source, and uses the radiation to illuminate a reticle holder. The radiation that passes through each reticle holder is then combined in an optical combiner, before passing through an imaging optics, which projects the combined radiation onto a semiconductor wafer.
An apparatus to facilitate exposing a wafer through at least two masks during an integrated circuit manufacturing process, comprising:
A method to facilitate exposing a wafer through at least two masks during an integrated circuit manufacturing process, comprising:
A system to facilitate exposing a wafer through at least two masks during an integrated circuit manufacturing process, comprising:
A method to improve chip yield during an integrated circuit manufacturing process, 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.
Mask illumination systems: multiple illumination paths, e.g. radiation distribution devices, microlens illumination systems, multiplexers or…
Mask projection systems: mask effects on the imaging process
Photomechanical production of textured or patterned surfaces
Term end not estimated
1. Field of the Invention
The invention relates to the process of manufacturing an integrated circuit. More specifically, the invention relates to a method and an apparatus for exposing a wafer using multiple masks during an integrated circuit manufacturing process.
2. Related Art
FIG. 1 illustrates the process of exposing a target wafer through a mask.
FIG. 2 illustrates projecting an image defined by a pair of masks onto a target in accordance with an embodiment of the invention.
FIG. 3 illustrates projecting an image defined by a pair of masks onto a target using multiple light sources in accordance with an embodiment of the invention.
Projecting a Pair of Masks
FIG. 2 illustrates projecting an image defined by a pair of masks onto a target in accordance with an embodiment of the invention. Source 202, which can be any suitable source of radiation such as a laser, provides radiation for the system. This radiation passes through illumination optics 204 to beam splitter 206 where the radiation is split into two beams; a first beam directed toward mask 208 and a second beam directed toward optical device 212. Note that optical device 212 could be placed in the first beam instead of the second beam. Optionally, optical device 212 could be placed after mirror 213 or mirror 210. Note that these optical structures are inside a single stepper/scanner system.
Optical device 212 can perform many functions. Optical device 212 can control the phase delay of the beam to compensate for path differences between illumination optics 204 and imaging optics 218. Optical device 212 can also control the phase of the beam to provide a phase shifted coherent beam at imaging optics 218. Using phase shifted coherent beams allows using two 0-degree dark field masks, with one beam shifted by 180 degrees, in place of a single dark field mask with both 0-degree and 180-degree phase shifts.