Thermal dynamic response sensing systems for heaters

Patent metadata

Field	Value
Publication number	US-10163668-B2
Application number	US-201414530670-A
Country	US
Kind code	B2
Filing date	Oct 31, 2014
Priority date	Aug 30, 2011
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A heater system includes a heater assembly, an imaging device and a control system. The heater assembly includes a plurality of heating zones. The imaging device acquires an image of the heater assembly. The control system determines variations in the plurality of heating zones based on the thermal image.

First claim

What is claimed is:

1. A heater system comprising:
a heater assembly including a heating surface for heating a heating target, the heating surface defining a plurality of heating zones;
an imaging device that acquires a thermal image of the heating surface of the heater assembly; and
a control system that determines variations in the plurality of heating zones based on the thermal image of the heating surface, wherein the thermal image includes a plurality of pixels corresponding to the plurality of heating zones in the heater assembly.

2. The heater system according to claim 1 , wherein the imaging device is one of an infrared camera and a video camera.

3. The heater system according to claim 1 , wherein the plurality of pixels represent temperatures of the plurality of heating zones.

4. The heater system according to claim 3 , wherein the control system is configured to determine that variations in at least one of the heating zones occur when at least one of pixels has a color different from that of adjacent pixels.

5. The heater system according to claim 4 , wherein the control system comprises:
a mapping unit to determine from the thermal image the heating zone of the identified variations;
a calculating unit to determine a difference between the actual temperature and a predetermined temperature in the heating zone; and
a heater controller to control the heating elements in the heating zone differently according to the mapping unit and the calculating unit to achieve a predetermined temperature profile across the heater assembly.

6. The heater system according to claim 1 , wherein the heater assembly further comprises a plurality of heating elements that are disposed in the plurality of heating zones and that are independently controllable.

7. The heater system according to claim 6 , wherein the control system selectively activates, deactivates or changes a power to the heating elements in the plurality of heating zones to compensate for the variations.

8. The heater system according to claim 1 , wherein the imaging device is a video camera that is configured to identify a location of a new load that is placed on the heating surface of the heater assembly.

9. The heater system according to claim 8 , wherein the control system further includes a processing unit that determines specific heating zones in the heater assembly in which the new load is located based on the thermal image.

10. The heater system according to claim 9 , wherein the control system selectively activates or increases a power to heating elements in the specific heating zones.

11. The heater system according to claim 1 , wherein the heater assembly includes a base heater layer that provides primary heating and a tuning heater layer that provides supplemental heating.

12. A heater system comprising:
a heater assembly having a heating surface and a plurality of heating elements for heating a heating target;
a controller that is configured to provide stimulus, causing a disturbance to a predetermined temperature of the heating surface of the heater assembly; and
a control system configured to be in electrical communication with the controller to receive stimulus information from the controller and to control the heater assembly to maintain predetermined temperature profile on the heating surface of the heater assembly based on the stimulus information from the controller.

13. The heater system according to claim 12 , wherein the controller is a gas controller that controls gas injection through a gas shower head proximate the heater assembly.

14. The heater system according to claim 13 , wherein the control system further comprises:
a calculating unit in communication with the gas controller and analyzing the gas injection includes at least one of type, mass, temperature, and timing of the gas to be injected proximate the heater assembly to calculate an anticipated disturbance to the predetermined temperature profile; and
a heater controller configured to be in electrical communication with the calculating unit to activate or change the power to each of the heating elements in response to the anticipated disturbance to compensate for the anticipated disturbance for maintaining the predetermined temperature profile.

15. The heater system according to claim 14 , wherein the heater assembly is disposed in a processing chamber and the gas controller controls the injection of gas into the processing chamber.

16. The heater system according to claim 12 , wherein the control system adjusts power to the heater assembly to compensate for the disturbance.

17. A heater system comprising:
a processing chamber defining an interior wall;
a heater assembly disposed on the interior wall and the heater assembly defining a heating surface including a plurality of heating zones and a plurality of heating elements, the heating surface defining an interior surface of the processing chamber; and
a control system configured to be in electrical communication with the heater assembly for monitoring a temperature distribution of the heating surface, wherein the control system by monitoring the electrical resistance of the heating elements determines the temperature distribution of the plurality of heating zones.

18. The heater system according to claim 17 , wherein the control system further includes an infrared camera for generating thermal images.

19. The heater system according to claim 18 , wherein the control system is configured to determine that cleaning of the processing chamber is not completed when variations exist between the temperature distribution of the plurality of heating zones based on the thermal image of the heating surface.

Assignees

• Watlow Electric Mfg

Inventors

• Steinhauser Louis P

Classifications

• H10P72/0606

  Position monitoring, e.g. misposition detection or presence detection · CPC title

• H10P72/0434

  mainly by convection · CPC title

• H10P72/0432

  mainly by conduction · CPC title

• H10P72/72

  using electrostatic chucks · CPC title

• H10P72/0602 Primary

  Temperature monitoring · CPC title