Device and method for controlling temperature of a mounting table, a program therefor, and a processing apparatus including same

• US 20060219360A1
• Filed: 03/31/2006
• Published: 10/05/2006
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Iwasaki, Masahide
• Granted Patent: US 7,789,962 B2
• Time in Patent Office: Days
• US Class Current: 156/345.270
• CPC Class Codes: G05D 23/1902 characterised by the use of a variable reference value
• CPC Class Codes: H01J 37/32724 Temperature
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 21/67248 Temperature monitoring

Abstract

A device for controlling a temperature of a mounting table for mounting thereon a target object includes a first and a second coolant passageway provided at the mounting table, a coolant circulator for circulating a coolant in the first and the second coolant passageway, channels, a coolant temperature controller for raising or lowering the temperature of the coolant, a channel switching unit for connecting, blocking and changing the channels among a first to a fourth port; and a channel controller. Various modes for controlling a temperature of the mounting table can be obtained by combining an ON/OFF state of the heating operation in the coolant temperature controller with ON/OFF states of opening/closing valves in the channel switching unit under the control of the channel controller.

Claims

1. A device for controlling a temperature of a mounting table for mounting thereon a target object, the device comprising:

a first and a second coolant passageway provided at the mounting table, each having an inlet and an outlet;

a coolant circulator having an output port connected to the inlet of the first coolant passageway via a first channel and a return port connected to the outlet of the second coolant passageway via a second channel, for circulating a coolant in the first and the second coolant passageway and outputting the coolant that has returned to the return port through the output port after restoring a temperature of the coolant to a reference temperature;

a coolant temperature controller provided in the middle of the first channel, for raising or lowering the temperature of the coolant from the reference temperature to a desired set temperature;

a channel switching unit having a first port connected to the outlet of the first coolant passageway via a third channel, a second port connected to a first branchpoint provided at an upstream side of the coolant temperature controller of the first channel via a fourth channel, a third port connected to the inlet of the second coolant passageway via a fifth channel and a fourth port connected to a second branchpoint provided in the second channel via a sixth channel, the channel switching unit for connecting, blocking and changing the channels among the first to the fourth port; and

a channel controller for connecting, blocking and changing the channels inside the channel switching unit.

2. The device of claim 1, wherein the channel switching unit has a first opening/closing valve connected between the first port and the third port, a second opening/closing valve connected between the first port and the fourth port, a third opening/closing valve connected between the second port and the third port and a fourth opening/closing valve connected between the second port and the fourth port, and

the channel controller controls on/off operations of the first to the fourth opening/closing valve.

3. The device of claim 1, wherein the channel switching unit has a first direction switching valve for connecting the first port to either the third or the fourth port and a second direction switching valve for connecting the second port to either the third or the fourth port, and

the channel controller controls states of respective channels inside the first and the second direction switching valve.

4. The device of claim 1, wherein the coolant temperature controller includes:

an inline heater attached to the first channel;

a temperature sensor provided at a downstream side of the inline heater, for detecting a coolant temperature in the first channel; and

a temperature controller for controlling a heat discharge rate of the inline heater so that the coolant temperature detected by the temperature sensor becomes equal to the set temperature.

5. The device of claim 4, wherein the inline heater heats a coolant in the first channel at a place near to the mounting table.

6. The device of claim 1, further comprising a flow rate control valve provided at a downstream side of the first branchpoint of the first channel, for variably controlling a flow rate of the coolant.

7. The device of claim 1, wherein the first and the second coolant passageway are concentrically disposed about a center of the mounting table.

8. The device of claim 1, wherein the first coolant passageway is provided in a central region of the mounting table, whereas the second coolant passageway is provided in a peripheral region of the mounting table.

9. The device of claim 1, wherein the coolant circulator includes a pump for circulating a coolant, a freezer for freezing the coolant that has just returned and a heater for heating the frozen coolant to a predetermined reference temperature.

19. A processing apparatus comprising:

a depressurizable chamber for accommodating therein a mounting table for mounting thereon a target object;

the device described in claim 1, for controlling a temperature of the mounting table;

a gas exhaust unit for exhausting the chamber; and

a processing gas supply unit for supplying a processing gas into the chamber.

20. The apparatus of claim 19, further comprising a plasma source for generating or supplying a plasma of the processing gas in the chamber.

21. The apparatus of claim 20, further comprising a first high frequency power supply unit for supplying a first high frequency power.

22. The apparatus of claim 21, further comprising a facing electrode facing the mounting table in the chamber and a second high frequency power supply unit for supplying a second high frequency power to the facing electrode.

23. The apparatus of claim 19, wherein the mounting table includes an electrostatic chuck for electrostatically adsorbing the target object and a thermally conductive gas supply line for supplying a thermally conductive gas between a backside surface of the target object and a mounting surface.

24. The apparatus of claim 20, wherein the coolant temperature controller raises a temperature of the target object to a set processing temperature by heating a coolant flowing in the first channel before a desired plasma processing is performed on the target object and, then, the coolant temperature controller gradually reduces the heating for the coolant flowing in the first channel so that the temperature of the target object is substantially maintained at the set processing temperature until the processing is completed.

10. A method for controlling a temperature of a mounting table by circulating a coolant coming out of a coolant circulator in a first and a second coolant passageway provided at the mounting table for mounting thereon a target object, the method comprising a first temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in parallel between an output port and a return port of the coolant circulator;

making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first coolant passageway after raising or lowering the temperature thereof to a desired set temperature; and

making a residual coolant flow in the second coolant passageway while substantially maintaining the reference temperature thereof.

11. The method of claim 10, further comprising a second temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in parallel between the output port and the return port of the coolant circulator;

making a part of the coolant outputted from the coolant circulator flow in the first coolant passageway while substantially maintaining the reference temperature thereof; and

making a residual coolant flow in the second coolant passageway while substantially maintaining the reference temperature thereof,

wherein the first and the second temperature control mode may be switched depending on processing conditions for the target object.

12. The method of claim 11, further comprising a third temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator;

making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first and the second coolant passageway sequentially after raising or lowering the temperature thereof to a desired set temperature; and

making a residual coolant bypass the coolant passageways,

wherein the first to the third temperature control mode may be switched depending on processing conditions for the target object.

13. The method of claim 11, further comprising a fourth temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator; and

making the entire coolant of the reference temperature outputted from the coolant circulator flow in the first and the second coolant passageway sequentially after raising or lowering the temperature thereof to a desired set temperature;

wherein the first, the second and the fourth temperature control mode may be switched depending on processing conditions for the target object.

14. The method of claim 12, further comprising a fifth temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator;

making a part of the coolant outputted from the coolant circulator flow in the first and the second coolant passageway sequentially while substantially maintaining the reference temperature thereof; and

making a residual coolant bypass the coolant passageways,

wherein the first, the third, and the fifth temperature control mode may be switched depending on processing conditions for the target object.

15. The method of claim 13, further comprising a fifth temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator;

making a part of the coolant outputted from the coolant circulator flow in the first and the second coolant passageway sequentially while substantially maintaining the reference temperature thereof; and

making a residual coolant bypass the coolant passageways,

wherein the first, the fourth, and the fifth temperature control mode may be switched depending on processing conditions for the target object.

16. The method of claim 12, further comprising a sixth temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator; and

making the entire coolant outputted from the coolant circulator flow in the first and the second coolant passageway sequentially while substantially maintaining the reference temperature thereof,

wherein the first, the third, and the sixth temperature control mode may be switched depending on processing conditions for the target object.

17. The method of claim 13, further comprising a sixth temperature control mode including the steps of:

connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator; and

making the entire coolant outputted from the coolant circulator flow in the first and the second coolant passageway sequentially while substantially maintaining the reference temperature thereof,

wherein the first, the fourth, and the sixth temperature control mode may be switched depending on processing conditions for the target object.

18. A method for controlling a temperature of a mounting table by circulating a coolant with a coolant circulator in a first and a second coolant passageway provided at the mounting table for mounting thereon a target object, the method comprising:

a first temperature control mode for controlling the temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in parallel between an output port and a return port of the coolant circulator, making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first coolant passageway after raising or lowering the temperature thereof to a desired set temperature, and making a residual coolant flow in the second coolant passageway while substantially maintaining the reference temperature thereof;

a second temperature control mode for controlling the temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in parallel between the output port and the return port of the coolant circulator, making a part of the coolant outputted from the coolant circulator flow in the first coolant passageway while substantially maintaining the reference temperature thereof, and making a residual coolant flow in the second coolant passageway while substantially maintaining the reference temperature thereof;

a third temperature control mode for controlling the temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator, and making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first and the second coolant passageway sequentially after raising or lowering the temperature thereof to a desired set temperature, and making a residual coolant bypass the coolant passageways;

a fifth temperature control mode for controlling the temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator, making a part of the coolant outputted from the coolant circulator flow in the first and the second coolant passageway sequentially while substantially maintaining the reference temperature thereof, and bypassing a residual coolant,

wherein the method performs a switching between the first mode and at least one of the second, the third and the fifth mode.

25. A program for controlling a temperature of a mounting table by circulating a coolant with a coolant circulator in a first and a second coolant passageway provided at a mounting table for mounting thereon a target object, wherein the program executes the steps of:

controlling a temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in parallel between an output port and a return port of the coolant circulator, making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first coolant passageway after raising or lowering the temperature thereof to a desired preset temperature, and making a residual coolant flow in the second coolant passageway while substantially maintaining the reference temperature thereof; and

controlling a temperature of the mounting table by connecting the first coolant passageway and the second coolant passageway in series between the output port and the return port of the coolant circulator, making a part of the coolant of a reference temperature outputted from the coolant circulator flow in the first and the second coolant passageway sequentially after raising or lowering the temperature thereof to a desired set temperature or while substantially maintaining the reference temperature thereof, and making a residual coolant thereof bypass the coolant passageways.