Monitoring stage alignment and related stage and calibration target
AssigneeInternational Business Machines Corporation
InventorsShahin Zangooie, Lin Zhou, Roger M. Young, Clemente Bottini, Ronald D. Fiege
Life of this patent
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Abstract
Methods, apparatuses and systems for monitoring a stage alignment in a processing system are disclosed. A method for monitoring a stage alignment in a processing system may include providing a calibration target on a surface of the stage; measuring an angle of incident of a light beam to the calibration target; and monitoring the stage alignment based on the determined angle of incidence.
Claims19
A method for monitoring a stage alignment in a processing system, the method comprising:
- providing a calibration target on a surface of the stage, the calibration target having:
- an upper surface including a portion sensitive to a change of an angle of incidence of a light beam striking on the portion;
- a lower surface which when interfacing with a surface of an object, translates a shape of the object surface into a relative position of the sensitive portion to the light beam;
- and
- a cut-off portion between the upper surface and the lower surface, the cut-off portion substantially perpendicular to the surface of the stage,
- wherein the sensitive portion of the upper surface includes one of a convex portion or a concave portion;
- measuring an angle of incidence of the light beam to the calibration target;
- and
- monitoring the stage alignment based on the determined angle of incidence.
A stage in a processing system, the stage comprising:
- a calibration target embedded in the stage, the calibration target including:
- an upper surface including a portion sensitive to a change of an angle of incidence of a light beam striking on the portion;
- a lower surface which when interfacing with a surface of an object, translates a shape of the object surface into a relative position of the sensitive portion to the light beam and
- a cut-off portion between the upper surface and the lower surface, the cut-off portion substantially perpendicular to the surface of the stage.
A calibration target comprising:
- an upper surface including a portion sensitive to a change of an angle of incidence of a light beam striking on the portion;
- a lower surface which when interfacing with a surface of an object, translates a shape of the object surface into a relative position of the sensitive portion to the light beam;
- and
- a cut-off portion between the upper surface and the lower surface the cut-off portion substantially perpendicular to the surface of the stage,
- wherein the sensitive portion of the upper surface includes one of a convex portion or a concave portion.
A system for monitoring a stage alignment in a processing system, the system comprising:
- a calibration target capable of being positioned on a surface of the stage, the calibration target having:
- an upper surface including a portion sensitive to a change of an angle of incidence of a light beam striking on the portion;
- a lower surface which when interfacing with a surface of an object, translates a shape of the object surface into a relative position of the sensitive portion to the light beam;
- and
- a cut-off portion between the upper surface and the lower surface, the cut-off portion substantially perpendicular to the surface of the stage,
- wherein the sensitive portion of the upper surface includes one of a convex portion or a concave portion;
- an angle of incidence mechanism configured to measure an angle of incidence of the light beam to the calibration target;
- and
- an alignment monitoring unit configured to monitor the stage alignment based on the determined angle of incidence measured by the angle of incidence mechanism.
Dependencies are inferred from the claim text.