Temperature control apparatus and method with recirculated coolant

A temperature control system for individually regulating the temperatures of a plurality of semiconductor workstations, the temperature control system comprising:

• a central source of a temperature regulating fluid in flow communication with each of the plurality of workstations for transporting fluid to each workstation and independently controlling temperature at each workstation,
• a plurality of heaters, each heater being associated with a workstation in a manner effective to heat the fluid transported to one of the individual workstations from the central source, whereby the temperature of the fluid provided to each workstation is controlled independently of fluid transported to other workstations of the system,
• a temperature differential determining system capable of determining the differential between the temperature of at least one workstation and an individual predetermined temperature, and
• a temperature controller selecting an operating sequence based on the temperature differential, so that when the temperature differential is above a predetermined value, an increased rate of flow of the fluid relative to a normal flow rate is transported to the workstation through a rapid temperature response bypass conduit that bypasses a heater corresponding to the workstation to rapidly cool the workstation below the predetermined value, and when the temperature differential is below a predetermined value, the heater corresponding to the workstation is modulated in order to maintain the temperature of the workstation using said normal rate of flow of the fluid without bypassing the heater.