Method for mapping wafers in a wafer carrier
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorLee-Chuan Tseng
Life of this patent
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Abstract
A method includes generating a first beam of radiation toward a first slot of a workpiece carrier. The first beam of radiation has a first beam area that is greater than or equal to an area of an opening of the first slot. The method further includes measuring a reflected portion of the first beam of radiation that is reflected toward, and impinges on, a radiation sensor. The method further includes determining if the first slot of the workpiece carrier is holding a workpiece based on the measured reflected portion of the first beam of radiation.
Claims20
A process tool comprising:
- a radiation source configured to generate a first beam of radiation toward a workpiece carrier having a first workpiece slot and a second workpiece slot;
- a radiation sensor adjacent to the radiation source and configured to measure a reflected portion of the first beam that is reflected toward the radiation sensor;
- sensor control circuitry coupled to the radiation sensor and configured to determine whether the first workpiece slot is holding a workpiece based on a measurement taken by the radiation sensor;
- and
- a focusing device arranged between the radiation source and the workpiece carrier and configured to adjust the first beam from a first state in which the first beam covers the first workpiece slot to a second state in which the first beam covers both the first workpiece slot and the second workpiece slot.
A process tool comprising:
- a radiation source configured to generate a first beam and a second beam of radiation toward a workpiece carrier having a first workpiece slot and a second workpiece slot;
- a radiation sensor adjacent to the radiation source and configured to measure a reflected portion of the first beam and a reflected portion of the second beam that are reflected by the workpiece carrier;
- sensor control circuitry coupled to the radiation sensor and configured to determine whether the first workpiece slot is holding a workpiece based on a measurement taken by the radiation sensor;
- a focusing device arranged between the radiation source and the workpiece carrier;
- and
- an actuator configured to move the focusing device so an area of the first beam encompasses an area of an opening of the first workpiece slot and an area of the second beam encompasses both the area of the opening of the first workpiece slot and the area of the opening of the second workpiece slot.
A method comprising:
- generating a first beam and a second beam of radiation toward a workpiece carrier having a first workpiece slot and a second workpiece slot;
- measuring a reflected portion of the first beam and a reflected portion of the second beam that are reflected by the workpiece carrier;
- and
- determining whether the first workpiece slot is holding a workpiece based on the measured reflected portion of the first beam or the measured reflected portion of the second beam,
- wherein the first beam encompasses the first workpiece slot and the second beam encompasses both the first workpiece slot and the second workpiece slot.
Dependencies are inferred from the claim text.