公开(公告)号：US10692749B2

公开(公告)日：2020-06-23

申请号：US15831972

申请日：2017-12-05

Applicant: Axcelis Technologies, Inc.

Inventor： Edward K. McIntyre ,  William P. Reynolds

IPC: H01L21/683 ,  H02N13/00 ,  G01R19/14 ,  G01R22/10 ,  H01L21/67 ,  H01L21/687

Abstract: An electrostatic clamp monitoring system has an electrostatic clamp configured to selectively electrostatically clamp a workpiece to a clamping surface associated therewith via one or more electrodes. A power supply is electrically coupled to the electrostatic clamp and configured to selectively supply a clamping voltage at a clamping frequency to the electrostatic clamp. A data acquisition system measures a current supplied to the one or more electrodes, and a controller integrates the measured current over time, therein determining a charge value associated a clamping force between the workpiece and electrostatic clamp. The controller is further configured to selectively vary one or more of the clamping voltage and clamping frequency based on the determined charge value, thereby maintaining a desired clamping force between the workpiece and electrostatic clamp.

公开(公告)号：US20190172743A1

公开(公告)日：2019-06-06

申请号：US15831972

申请日：2017-12-05

Applicant: Axcelis Technologies, Inc.

Inventor： Edward K. McIntyre ,  William P. Reynolds

IPC: H01L21/683 ,  G01R22/10 ,  G01R19/14 ,  H02N13/00

Abstract: An electrostatic clamp monitoring system has an electrostatic clamp configured to selectively electrostatically clamp a workpiece to a clamping surface associated therewith via one or more electrodes. A power supply is electrically coupled to the electrostatic clamp and configured to selectively supply a clamping voltage at a clamping frequency to the electrostatic clamp. A data acquisition system measures a current supplied to the one or more electrodes, and a controller integrates the measured current over time, therein determining a charge value associated a clamping force between the workpiece and electrostatic clamp. The controller is further configured to selectively vary one or more of the clamping voltage and clamping frequency based on the determined charge value, thereby maintaining a desired clamping force between the workpiece and electrostatic clamp.