Measurement method and measuring jig
In a measurement method, a terminal is brought into contact with an electrode in an electrostatic chuck in contact with a substrate that is grounded. Further, the terminal, the electrostatic chuck and the substrate are fixed, and a current value and a voltage value are measured using an ammeter and a voltmeter, respectively, that are connected to the terminal. In addition, whether or not the terminal and the electrode are electrically connected is determined from a slope of the current value and/or a peak current value based on the measured current value and the voltage value.
1. A measurement method comprising:
mounting a substrate on an electrostatic chuck;
supplying a gas into a space above the substrate within a chamber;
measuring a discharge start voltage value and a current value while a gas discharge is generated in the chamber without generation of plasma;
calculating an electrostatic capacitance of the electrostatic chuck from the measured discharge start voltage value and the measured current value; and
comparing the calculated electrostatic capacitance of the electrostatic chuck with a predetermined threshold of the electrostatic capacitance and determining a state in the chamber based on the comparison result.
2. A measurement method of claim 1 , further comprising:
determining whether or not an electrode in the electrostatic chuck and a terminal brought into contact with the electrode are electrically connected from a slope of the current value and/or a peak current value based on the measured discharge start voltage value and the measured current value.
3. The measurement method of claim 2 , wherein the substrate is made of a silicon-containing material or a metal, and is grounded.
4. The measurement method of claim 2 , further comprising:
providing an RC filter between the terminal and an ammeter that measure the current value and cutting off a current in a predetermined frequency band.
5. The measurement method of claim 1 , wherein the gas discharge is generated by applying a voltage to an electrode in the electrostatic chuck in a state where a base of the electrostatic chuck and the substrate on the electrostatic chuck are in a floating state.
6. The measurement method of claim 1 , wherein the gas discharge is generated by generating a voltage difference between the electrostatic chuck and an upper electrode disposed to be opposite to the electrostatic chuck.
7. The measurement method of claim 1 , wherein a substrate attractive force of the electrostatic chuck is determined based on the comparison result.
8. The measurement method of claim 1 , wherein whether or not it is necessary to perform cleaning and/or treatment is determined based on the comparison result.
9. The measurement method of claim 1 , wherein the gas is an inert gas.
10. A measurement method comprising:
mounting a substrate on an electrostatic chuck;
supplying a gas into a space above the substrate within a chamber; and
measuring a discharge start voltage value and a current value while a gas discharge is generated in the chamber without generation of plasma,
wherein the electrostatic chuck is divided into multiple zones, and an electrostatic capacitance of each of the multiple zones is calculated,
wherein the gas discharge is generated by applying a voltage to an electrode disposed in the electrostatic chuck below an edge ring mounted on an edge ring mounting surface of the electrostatic chuck in a state where a base of the electrostatic chuck and the edge ring are in a floating state, and an electrostatic capacitance of the edge ring mounting surface of the electrostatic chuck is calculated.