Temperature control system for a workpiece chuck

A method of controlling temperature in a workpiece chuck, comprising:

• connecting a circulating unit to the chuck to circulate a temperature control fluid through the chuck, the temperature control fluid being used to control the temperature of the chuck;
• coupling a refrigeration system to the temperature control fluid;
• connecting a fluid carrying system to the circulating unit and the chuck to circulate the temperature control fluid through the chuck, the fluid carrying system comprising a plurality of at least partially separated fluid paths connected to a respective plurality of fluid input ports in an upper portion of the chuck and a lower member under the upper portion such that temperature is separately controlled in the upper portion and the lower member;
• sensing a temperature of the temperature control fluid circulated to the upper portion and the lower member;
• sensing a temperature of the upper portion and the lower member;
• using the sensed temperatures of the temperature control fluid and the upper portion and the lower member to control temperature of the temperature control fluid circulated to the upper portion and the lower member and the temperature of the upper portion and the lower member in controlling temperature of the temperature control fluid, controlling the fluid carrying system to switch a flow path of the temperature control fluid such that the temperature control fluid at least partially bypasses the refrigeration system.

A temperature control system for a workpiece chuck, comprising:

• a circulating unit connected to the chuck for circulating a temperature control fluid through the chuck, the temperature control fluid being used to control the temperature of the chuck;
• a refrigeration system in thermal communication with the temperature control fluid, the refrigeration system including first and second heat exchangers for exchanging heat with the temperature control fluid;
• a fluid carrying system connected to the circulating unit and the chuck for circulating the temperature control fluid through the chuck, the fluid carrying system comprising a plurality of at least partially separated fluid paths connected to a respective plurality of fluid input ports in an upper portion of the chuck and a lower member under the upper portion such that temperature is separately controlled in the upper portion and the lower member;
• a plurality of temperature sensors for sensing the temperature of the temperature control fluid circulated to the upper portion and the lower member and the temperature of the upper portion and the lower member, the plurality of temperature sensors generating a respective plurality of temperature signals;
• and
• a controller coupled to the refrigeration system for coupling hot gas around the first heat exchanger to the second heat exchanger to bypass at least partially the first heat exchanger to heat the temperature control fluid, the controller being coupled to the temperature sensors for receiving the temperature signals from the temperature sensors, the controller using the temperature signals to control the temperature of the temperature control fluid circulated to the upper portion and the lower member and the temperature of the upper portion and the lower member, the controller also being coupled to the fluid carrying system such that the controller, in controlling the temperature of the temperature control fluid, can switch a flow path of the temperature control fluid such that the temperature control fluid at least partially bypasses the refrigeration system.

A method of controlling temperature in a workpiece chuck, comprising:

• connecting a circulating unit to the chuck to circulate a temperature control fluid through the chuck, the temperature control fluid being used to control the temperature of the chuck;
• connecting a fluid carrying system to the circulating unit and the chuck to circulate the temperature control fluid through the chuck, the fluid carrying system comprising a plurality of at least partially separated fluid paths connected to a respective plurality of fluid input ports in an upper portion of the chuck and a lower member under the upper portion such that temperature is separately controlled in the upper portion and the lower member;
• coupling a refrigeration system to the temperature control fluid;
• providing first and second heat exchangers in the refrigeration system for exchanging heat with the temperature control fluid;
• sensing a temperature of the temperature control fluid circulated to the upper portion and the lower member;
• sensing a temperature of the upper portion and the lower member;
• using the sensed temperatures of the temperature control fluid and the upper portion and the lower member to control temperature of the temperature control fluid circulated to the upper portion and the lower member and the temperature of the upper portion and the lower member;
• in controlling the temperature of the temperature control fluid, controlling the fluid carrying system to switch a flow path of the temperature control fluid such that the temperature control fluid at least partially bypasses the refrigeration system;
• and
• coupling hot gas around the first heat exchanger to the second heat exchanger to bypass at least partially the first heat exchanger to heat the fluid.