Patent ID: 11972971
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A method, comprising:
generating, by a pressure sensor included in a wafer lift pin system, pressure sensor data associated with a gas in the wafer lift pin system;
providing, by the pressure sensor, the pressure sensor data to a controller included in the wafer lift pin system;
determining, by the controller and based on the pressure sensor data, that a first pressure of the gas satisfies a pressure threshold;
transmitting, by the controller and based on determining that the first pressure of the gas satisfies the pressure threshold, an indication of a second pressure to a proportional valve included in the wafer lift pin system; and
purging, by the proportional valve, the gas from one or more lift pins approximately at the second pressure to cause the one or more lift pins to retract below a wafer stage,
wherein purging the gas from the one or more lift pins comprises dynamically adjusting, by the proportional valve, a rate at which the gas is purged from the one or more lift pins to achieve the second pressure, and
wherein the retracting the one or more lift pins causes a semiconductor wafer, supported on the one or more lift pins, to be lowered onto the wafer stage.