Electrostatic chuck, substrate processing apparatus, and method of manufacturing semiconductor device using the same
An electrostatic chuck, a substrate processing apparatus, and a method of manufacturing a semiconductor device are provided. The electrostatic chuck comprises a chuck base, an insulation plate on the chuck base, a first heater comprising a cell heater in the insulation plate, and a heater controller configured to control the cell heater. The heater controller obtains a resistance of the cell heater and compares the resistance with a threshold value to control a heating power provided to the cell heater.
1. A method of manufacturing a semiconductor device, the method comprising:
obtaining a threshold value of a plurality of cell heaters connected to fan electrodes in a insulation plate;
heating a substrate; and
etching the substrate,
wherein the heating the substrate comprises:
providing the plurality of cell heaters with a heating power;
measuring a resistance of the plurality of cell heaters; and
comparing the resistance with the threshold value to control the heating power,
wherein the fan electrodes comprise:
a plurality of power electrodes configured to provide the heating power to the plurality of cell heaters; and
a ground electrode disposed between the plurality of power electrodes and configured to ground the plurality of cell heaters,
wherein the plurality of power electrodes comprise:
a first outer electrode on a first side of the ground electrode;
a first inner electrode inside the first outer electrode in a central direction of the insulation plate;
a second outer electrode on a second side of the ground electrode; and
a second inner electrode inside the second outer electrode in the central direction of the insulation plate,
wherein the ground electrode is disposed between the first inner electrode and the second inner electrode and between the first outer electrode and the second outer electrode.
2. The method of claim 1 , wherein the comparing the resistance with the threshold value comprises:
determining whether the resistance is greater than the threshold value; and
holding heating of the substrate when the resistance is greater than the threshold value.
3. The method of claim 2 , wherein, when the resistance is less than the threshold value, repeatedly performing, until the resistance becomes equal to the threshold value, providing the heating power, measuring the resistance, and comparing the resistance with the threshold value.
4. The method of claim 1 , wherein the measuring the resistance comprises:
providing a sensing power to the plurality of cell heaters; and
measuring a voltage between a first terminal and a second terminal of the plurality of cell heaters.
5. The method of claim 1 , wherein obtaining the threshold value of the plurality of cell heaters comprises;
heating a test substrate;
measuring the resistance of the plurality of cell heaters;
etching the test substrate;
obtaining a difference in an etch rate of the test substrate; and
obtaining the threshold value of the plurality of cell heaters, wherein the threshold value, when applied, are sufficient to remove the difference in the etch rate.