Auto-calibration to a station of a process module that spins a wafer
AssigneeLam Research Corporation
InventorsJacob L. Hiester, Richard Blank, Peter Thaulad, Paul Konkola
Life of this patent
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Abstract
A method for calibration including determining a temperature induced offset in a pedestal of a process module under a temperature condition for a process. The method includes delivering a wafer to the pedestal of the process module by a robot, and detecting an entry offset. The method includes rotating the wafer over the pedestal by an angle. The method includes removing the wafer from the pedestal by the robot and measuring an exit offset. The method includes determining a magnitude and direction of the temperature induced offset using the entry offset and exit offset.
Claims20
A system for processing wafers, comprising:
- a process module including a rotation device having a rotation axis;
- a pedestal within the process module configured for supporting a wafer;
- a transfer module (TM) robot configured for transferring the wafer to and from the process module within a reference coordinate system;
- and
- a measurement system fixed within the reference coordinate system, the measurement system configured to determine an entry offset of the wafer within the reference coordinate system when transferring the wafer to the process module, the measurement system configured to determine an exit offset of the wafer when transferring the wafer from the process module and after the wafer has been rotated within the process module by the rotation device when the process module is under a process condition, the entry offset and the exit offset being based on an initial calibrated location of the pedestal in the process module,
- wherein the measurement system is configured for determining a condition induced offset of the rotation axis based on the entry offset and the exit offset.
A method, comprising:
- determining an entry offset of a wafer within a reference coordinate system when transferring the wafer to a pedestal of a process module, the entry offset being based on an initial calibrated location of the pedestal;
- rotating the wafer within the process module using a rotation device;
- determining an exit offset of the wafer within the reference coordinate system when transferring the wafer from the pedestal of the process module, the exit offset being based on the initial calibrated location of the pedestal;
- and
- determining a condition induced offset of a rotation axis of the rotation device using the entry offset and the exit offset.
Dependencies are inferred from the claim text.