Gas temperature control for a plasma process

• US 20030084848A1
• Filed: 06/19/2002
• Published: 05/08/2003
• Est. Priority Date: 06/22/2001
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Long, Maolin
• Granted Patent: US 6,811,651 B2
• Time in Patent Office: Days
• US Class Current: 118/715
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: H01J 37/3244 Gas supply means

Abstract

A method and system for controlling the temperatures of at least one gas in a plasma processing environment prior to the at least one gas entering a process chamber. This temperature control may vary at different spatial regions of a showerhead assembly (either an individual gas species or mixed gas species). According to one embodiment, an in-line heat exchanger alters (i.e., increases or decreases) the temperature of passing gas species (either high- or low-density) prior to entering a process chamber, temperature change of the gases is measured by determining a temperature of the gas both upon entrance into the in-line heat exchanger assembly and upon exit.

Claims

1. An in-line heat exchanger apparatus for controlling the temperature of a gas comprising:

an inlet-side gas line for receiving a gas having a temperature to be controlled;

an outlet-side gas line for expelling the gas after the temperature of the gas has been controlled;

at least one temperature sensor for measuring the temperature of the gas;

a heat conductor including at least one of a heating element for heating the gas and a cooling element for cooling the gas;

an insulator surrounding an exterior of the heat conductor; and

at least one gas through-channel, coupled between the inlet-side gas line and the outlet side gas line and formed by voids in the heat conductor, for changing the temperature of the gas.

2. An in-line heat exchanger apparatus according to claim 1, wherein at least one of the heating element and the cooling element are helically wound within the heat conductor.

3. An in-line heat exchanger apparatus according to claim 1, further comprising a thermal transfer membrane interposed between the insulator and the heat conductor.

4. An in-line heat exchanger according to claim 1, wherein the heat conductor comprises a plurality of concentric voids separated by at least one of a thermal transfer membrane and a membrane support, thereby forming plural gas through channels between the inlet-side and outlet side gas lines.

5. An in-line heat exchanger apparatus according to claim 4, further comprising a thermal transfer membrane interposed between the insulator and the heat conductor.

6. An in-line heat exchanger according to claim 1, wherein the at least one temperature sensor comprises an inlet side temperature sensor and an outlet side temperature sensor.

7. An in-line heat exchanger according to claim 6, further comprising a controller for monitoring the temperature of the gas at the inlet side temperature sensor and the outlet side temperature sensor, and for changing a temperature of the heat conductor to change the temperature of the gas when the temperature of the gas falls outside a target range.

8. An in-line heat exchanger according to claim 7, wherein the heat conductor comprises the heating element for increasing the temperature of the gas when the temperature of the gas falls outside a target range.

9. An in-line heat exchanger according to claim 7, wherein the heat conductor comprises the cooling element for decreasing the temperature of the gas when the temperature of the gas falls outside a target range.

10. A gas injection process chamber comprising:

a plurality of gas lines;

a neck at which the plurality of gas lines are joined;

a process chamber; and

a temperature controller located between the neck and the process chamber.

11. A gas injection process chamber according to claim 10, further comprising:

a showerhead, and

a plurality of temperature controllers disposed along a plurality of inlets from the neck to the showerhead.

12. A gas injection process chamber comprising:

a process chamber;

a plurality of gas lines;

a plurality of temperature controllers each having an inlet side and an outlet side, a single temperature controller disposed into each gas line; and

a neck for joining the outlet sides of the plurality of temperature controllers prior to connecting to the process chamber.

13. A gas injection process chamber according to claim 12, further comprising:

a showerhead, and

a plurality of temperature controllers disposed along a plurality of inlets from the neck to the showerhead.

14. A method for operating a temperature controller coupled to a process chamber, the method comprising:

determining a process type;

supplying a process gas to the process chamber through an in-line heat exchange assembly, the process gas being determined from the process type;

determining a desired gas temperature for the process gas using the process type;

determining gas temperature in the in-line heat exchange assembly;

comparing the gas temperature to the desired gas temperature using a control unit coupled to the in-line heat exchange assembly; and

adjusting the gas temperature in the in-line heat exchange assembly when the comparison indicates that a temperature adjustment is required.

15. The method for operating a temperature controller coupled to a process chamber according to claim 14, the method further comprising:

supplying a second process gas to the process chamber through the in-line heat exchange assembly, the second process gas being determined from the process type;

determining a desired gas temperature for the process gasses using the process type;

determining gas temperature for the process gasses in the in-line heat exchange assembly;

comparing the gas temperature for the process gasses to the desired gas temperature for the process gasses using a control unit coupled to the in-line heat exchange assembly; and

adjusting the gas temperature for the process gasses in the in-line heat exchange assembly when the comparison indicates that a temperature adjustment is required.

16. The method for operating a temperature controller coupled to a process chamber according to claim 14, the method further comprising:

supplying a second process gas to the process chamber through a second in-line heat exchange assembly, the second process gas being determined from the process type;

determining a desired gas temperature for the second gas using the process type;

determining gas temperature for the second gas in the second in-line heat exchange assembly;

comparing the gas temperature for the second gas to the desired gas temperature for the second gas using a control unit coupled to the in-line heat exchange assembly; and

adjusting the gas temperature for the second gas in the second in-line heat exchange assembly when the comparison indicates that a temperature adjustment is required.