Method of temperature measurement used in radio-frequency processing apparatus for semiconductor
A method for temperature measurement used in an RF processing apparatus for semiconductor includes generating by electrodes an RF signal sequence having multiple discontinuous RF signals that are separated by a time interval; and generating a temperature sensing signal by a thermal sensor during the time interval.
1. A method of temperature measurement used in radio frequency (RF) processing apparatus for semiconductor, wherein the RF processing apparatus has a pair of electrodes for generating plasma and a heater for supporting wafer, the heater has at least one thermal sensor and at least one heating coil, the method comprising:
generating, by the pair of electrodes, an RF signal sequence that includes multiple discontinuous RF signals, wherein any one of the RF signals is separated from its next one with a time interval; and
generating, by the at least one thermal sensor, a sensing signal within the time intervals,
wherein the time interval is determined by a time constant associated with a heat resistance and a heat capacitance which are measured between a top surface of the heater and the at least one heating coil or between a top surface of the heater and the at least one thermal sensor, the time constant is the heat resistance multiplied by the heat capacitance.
2. The method as claimed in claim 1 , wherein the time interval is less than one tenth of the time constant.