Temperature control system and temperature control method

1. A temperature control system, comprising:

a stage configured to support a workpiece and provided with a heat exchange medium flow path formed within the stage, the heat exchange medium flow path including a first end and a second end, a heat exchange medium flowing from the first end to the second end of the heat exchange medium flow path;

a first valve;

a second valve;

a first heat exchange medium supply device including a supply port which supplies a first heat exchange medium adjusted to have a first temperature and a recovery port, the supply port being connected to the first end of the heat exchange medium flow path through the first valve;

a second heat exchange medium supply device including a supply port which supplies a second heat exchange medium adjusted to have a second temperature higher than the first temperature and a recovery port, the supply port of the second heat exchange medium supply device connected to the first end of the heat exchange medium flow path through the second valve; and

a controller which controls the first valve and the second valve such that the first heat exchange medium and the second heat exchange medium are alternately supplied to the first end of the heat exchange medium flow path, and stores a target temperature for the stage and a heat quantity for the stage required in achieving the target temperature in a memory,

wherein the controller includes:

a heat quantity acquiring controller which accesses the memory and acquires from the memory the heat quantity required in making a temperature of the stage become equal to the target temperature;

a supply time calculating controller which calculates, based on the required heat quantity received from the heat quantity acquiring controller, supply times of the first heat exchange medium and the second heat exchange medium alternately supplied to the heat exchange medium flow path; and

a valve controller which opens and closes the first valve and the second valve in accordance with the supply times calculated by the supply time calculating controller such that the first heat exchange medium and the second heat exchange medium are alternately supplied to the first end of the heat exchange medium flow path for the supply times calculated at the supply time calculating controller.

2. The system of claim 1 , wherein the recovery port of the first heat exchange medium supply device is coupled to the second end of the heat exchange medium flow path through a third valve, and

the recovery port of the second heat exchange medium supply device is coupled to the second end of the heat exchange medium flow path through a fourth valve.

3. The system of claim 2 , further comprising:

a temperature sensor configured to measure a temperature of the heat exchange medium flowing out from the second end of the heat exchange medium flow path.

4. The system of claim 3 , further comprising:

a circulation flow path through which the heat exchange medium flowing out from the second end of the heat exchange medium flow path is introduced into the first end of the heat exchange medium flow path,

wherein, if a difference between the target temperature and the temperature of the heat exchange medium measured at the temperature sensor is smaller than a specified threshold value, the valve controller controls the first valve, the second valve, the third valve and the fourth valve such that the heat exchange medium flowing out from the second end of the heat exchange medium flow path is re-introduced into the first end of the heat exchange medium flow path through the circulation flow path.

5. The system of claim 3 , wherein the valve controller is configured to control, based on the temperature of the heat exchange medium measured at the temperature sensor, the third valve and the fourth valve such that the first heat exchange medium supplied from the first end of the heat exchange medium flow path is introduced into the recovery port of the first heat exchange medium supply device through the second end of the heat exchange medium flow path and such that the second heat exchange medium supplied from the first end of the heat exchange medium flow path is introduced into the recovery port of the second heat exchange medium supply device through the second end of the heat exchange medium flow path.

6. The system of claim 1 , wherein, prior to controlling opening and closing of the first valve and the second valve such that the first heat exchange medium and the second heat exchange medium are alternately supplied to the heat exchange medium flow path, the valve controller is configured to: control the first valve and the second valve such that one heat exchange medium of the first heat exchange medium and the second heat exchange medium for making the temperature of the stage come close to the target temperature is continuously supplied to the first end of the heat exchange medium flow path; and control the first valve and the second valve such that, after a difference between the temperature of the stage and the target temperature falls within a predetermined range by the supply of the one heat exchange medium, the other heat exchange medium of the first heat exchange medium and the second heat exchange medium is supplied to the first end of the heat exchange medium flow path.

7. A temperature control method for use in a temperature control system,

the temperature control system including:

a stage configured to support a workpiece and provided with a heat exchange medium flow path formed within the stage, the heat exchange medium flow path including a first end and a second end, a heat exchange medium flowing from the first end to the second end of the heat exchange medium flow path;

a first valve;

a second valve;

a first heat exchange medium supply device including a supply port which supplies a first heat exchange medium adjusted to have a first temperature and a recovery port, the supply port being connected to the first end of the heat exchange medium flow path through the first valve;

a second heat exchange medium supply device including a supply port which supplies a second heat exchange medium adjusted to have a second temperature higher than the first temperature and a recovery port, the supply port of the second heat exchange medium supply device connected to the first end of the heat exchange medium flow path through the second valve; and

a controller which controls the first valve and the second valve such that the first heat exchange medium and the second heat exchange medium are alternately supplied to the first end of the heat exchange medium flow path, and stores a target temperature for the stage and a heat quantity for the stage required in achieving the target temperature in a memory,

the method comprising:

accessing the memory and acquiring from the memory the heat quantity required in making a temperature of the stage become equal to the target temperature;

calculating, based on the required heat quantity, supply times of the first heat exchange medium and the second heat exchange medium alternately supplied to the heat exchange medium flow path; and

controlling the first valve and the second valve to be opened and closed in accordance with the calculated supply times such that the first heat exchange medium and the second heat exchange medium are alternately supplied to the first end of the heat exchange medium flow path for the calculated supply times.