A semiconductor wafer temperature control apparatus

A temperature control apparatus for supplying fluid to control a temperature of at least one semiconductor wafer within a semiconductor processing chamber, said temperature control apparatus comprising:

• a mixed refrigerant refrigeration system;
• said temperature control apparatus being configured to supply said mixed refrigerant to at least one conditioning circuit within said semiconductor processing chamber and to receive said mixed refrigerant from said at least one conditioning circuit;
• wherein
• said temperature control apparatus comprises temperature control circuitry for controlling a temperature of said at least one conditioning circuit to one of a plurality of predetermined temperatures, at least one of said temperatures being below -100℃;
• said temperature control circuitry being configured to receive a signal indicative of a temperature of said at least one conditioning circuit from at least one temperature sensor and to control said temperature of said at least one conditioning circuit in dependence upon said received signal and said predetermined temperature by controlling at least one of a mass flow rate, composition or temperature of said mixed refrigerant supplied to said at least one conditioning circuit.