Systems and methods for reducing electrostatic charge of semiconductor wafers

A chemical-mechanical polishing machine, comprising:

• a head portion carrying a plurality of polishing pads and a transfer station proximate to the polishing pads, the transfer station being configured to store a semiconductor wafer and controllably release electrostatic charge on the wafer;
• and
• a base portion rotatably coupled to the head portion, the base portion carrying a plurality of wafer carriers individually corresponding to the polishing pads;
• wherein the transfer station includes a pedestal having a plurality of fluid ports facing the wafer, and wherein the chemical-mechanical polishing machine further includes a fluid supply system in fluid communication with the fluid ports via a supply line, the fluid supply system including a pressure control system for adjusting a pressure of the fluid supplied to the fluid ports to be less than about 40 psig;
• and
• wherein the pressure control system includes a controller having a computer-readable medium containing instructions for monitoring a fluid pressure in the supply line, accepting a pressure setpoint from an operator, and moving the measured fluid pressure toward the pressure setpoint, and wherein the transfer station includes a pedestal constructed from an electrostatic dissipative material having a surface resistivity of about 1×105 to about 1×1012 ohms and a volume resistivity of about 1×104 to about 1×1011 ohm-cm.

A chemical-mechanical polishing machine, comprising:

• a polishing pad;
• a wafer carrier configured to carry a semiconductor wafer in contact with the polishing pad;
• and
• a transfer station proximate to the polishing pad for holding the wafer during loading and/or unloading, the transfer station including a pedestal configured to carry the semiconductor wafer and controllably release electrostatic charges from the semiconductor wafer to ground without sparking and/or arcing, wherein:
• the pedestal includes an interface plate facing the wafer and a support coupled to the interface plate, the interface plate being constructed from an electrostatic dissipative material having a surface resistivity of about 1×105 to about 1×1012 ohms and a volume resistivity of about 1×104 to about 1×1011 ohm-cm, the support being electrically grounded;
• the pedestal also includes a plurality of fluid ports facing the semiconductor wafer;
• the chemical-mechanical polishing machine further includes a fluid supply system in fluid communication with the fluid ports via a supply line, the fluid supply system including a pressure control system that includes a control valve, a pressure sensor, and a controller operatively coupled to the control valve and the pressure sensor, the controller having a computer-readable medium containing instructions for monitoring a fluid pressure measured by the pressure sensor, accepting a pressure setpoint from an operator, and regulating the control valve to move the fluid pressure toward the pressure setpoint of about 15-20 psig.

A chemical-mechanical polishing machine, comprising:

• a polishing pad;
• a wafer carrier configured to carry a semiconductor wafer in contact with the polishing pad;
• and
• a transfer station proximate to the polishing pad for holding the semiconductor wafer during loading and/or unloading, the transfer station including a pedestal having an interface facing the wafer and a support proximate to the interface, the interface being constructed from an electrostatic dissipative material, the support being conductive and electrically grounded, wherein the pedestal is constructed from an electrostatic dissipative material having a surface resistivity of about 1×105 to about 1×1012 ohms and a volume resistivity of about 1×104 to about 1×1011 ohm-cm.