Apparatus for cooling a sputtering target

An apparatus for cooling a sputtering target, the apparatus comprising a heat sink which has a contact surface configured to form a mechanical contact with the sputtering target, wherein the heat sink is traversed by a cooling channel, wherein the heat sink includes a cooling channel inlet and a cooling channel outlet, and wherein the cooling channel comprises a fluid flowable through the cooling channel, wherein

• the cooling channel outlet is connected to an inlet of a compressor by a first pipe;
• an outlet of the compressor is connected to the inlet of a pressure stage by a second pipe;
• a first portion of the second pipe extends through a first heat exchanger;
• the outlet of the pressure stage is connected to the cooling channel inlet by a third pipe;
• the fluid is in the form of a refrigerant;
• wherein the refrigerant has a boiling point of 0° C. or less at a pressure of 1 bar and a boiling point of −10° C. or less at a pressure of 0.7 bar;
• and the pressure stage is configured to affect a pressure reduction of at least 2 bars on average over time from a pressure stage inlet to a pressure stage outlet.