Method of calibrating multiple chamber pressure sensors

A method of calibrating multiple chamber pressure sensors of a substrate processing system,

• wherein the substrate processing system comprises:
• a controller;
• multiple chambers;
• multiple chamber pressure sensors, each of which is installed so as to measure an internal pressure of a corresponding one of the multiple chambers;
• multiple gas suppliers, each of which is configured to supply a gas to an internal space of a corresponding one of the multiple chambers;
• multiple exhausters connected to the internal spaces of the multiple chambers via multiple exhaust flow paths, respectively;
• and
• multiple first gas flow paths, each of which connects a corresponding one of the multiple gas suppliers to a corresponding one of the multiple chambers,
• the method comprising:
• determining, by the controller, a third volume, which is a sum of a first volume of a first gas flow path selected from among the multiple first gas flow paths connected to a gas supplier selected from among the multiple gas suppliers and a second volume of the internal space of a chamber selected from among the multiple chambers and connected to the selected first gas flow path;
• acquiring, by the controller, a first pressure change rate of the internal space of the selected chamber, which is caused by allowing the gas having a preset flow rate to flow to the internal space of the selected chamber from the selected gas supplier via the selected first gas flow path, using a chamber pressure sensor for the selected chamber, which is selected from among the multiple chamber pressure sensors;
• calculating, by the controller, a second pressure change rate of the internal space of the selected chamber, which is caused by allowing the gas to flow in the acquiring the first pressure change rate, by using the preset flow rate of the gas caused to flow in acquiring the first pressure change rate and the first volume and regarding the gas caused to flow in the acquiring the first pressure change rate as an ideal gas;
• and
• calibrating, by the controller, the selected chamber pressure sensor such that a difference between the first pressure change rate and the second pressure change rate is within a preset range,
• wherein a sequence including the determining the third volume, the acquiring the first pressure change rate, the acquiring the second pressure change rate, and the calibrating the chamber pressure sensor is repeated, and
• wherein each of the selected chamber pressure sensor is sequentially selected from the multiple chamber pressure sensors and then the sequence which is repeated is performed with respect to the selected chamber pressure sensor.