System and method of verifying workpiece alignment
AssigneeAxcelis Technologies, Inc.
InventorYusef Nouri
Life of this patent
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Abstract
A workpiece processing system and method are disclosed for determining an alignment of a workpiece upon a workpiece support using a retractable sensor. A sensor moves in/out relative to an edge of the workpiece support to obtain positional data while the workpiece support is rotated. Based on the positional data, the alignment of the workpiece and workpiece support may be determined. After determining the alignment, the sensor may be retracted behind the workpiece support, such that the sensor is shielded by the workpiece support from an ion beam during ion implantation. Using a helical motion, an angle between the sensor and a support surface of the workpiece support may be maintained approximately constant during the measurement.
Claims9
A workpiece characterization system, comprising:
- a process chamber;
- a process medium source configured to generate a process medium along a process medium path;
- a workpiece support having a support surface defining a support plane, wherein the workpiece support is configured to selectively support a workpiece on the support surface and to selectively expose the workpiece to the process medium along the process medium path within the process chamber;
- a sensor;
- a coupling apparatus operably coupled to the sensor, wherein the coupling apparatus comprises a guide member and a sensor arm;
- and
- an actuator arranged downstream of the support plane when viewed along the process medium path, wherein the actuator is operably coupled to the coupling apparatus and configured to selectively translate the sensor along a curvilinear sensor path between a first position and a second position via the coupling apparatus, wherein the sensor is positioned downstream of the support plane in the first position when viewed along the process medium path, and wherein the sensor is positioned at least partially upstream of the support plane in the second position when viewed along the process medium path, wherein the sensor is configured to detect a peripheral edge of the workpiece in the second position, wherein the actuator is configured to selectively control a motion of the sensor arm with respect to the guide member, thereby controlling a motion of the sensor along the curvilinear sensor path, wherein the sensor arm has a first end portion and a second end portion, wherein the first end portion is operably coupled to the actuator and the second end portion is operably coupled to the sensor, and wherein the actuator is fixed with respect to the guide member and comprises a linear actuator configured to linearly translate a drive shaft along a drive axis, wherein the first end portion of the sensor arm is coupled to a distal end of the drive shaft, wherein the guide member comprises a helical groove, and wherein the drive shaft comprises a follower, wherein the follower slidingly engages the helical groove to define the curvilinear sensor path.
Dependencies are inferred from the claim text.