Temperature control in plasma processing apparatus using pulsed heat transfer fluid flow

摘要

Methods and systems for controlling temperatures in plasma processing chamber via pulsed application of heating power and pulsed application of cooling power. In an embodiment, temperature control is based at least in part on a feedforward control signal derived from a plasma power input into the processing chamber. In further embodiments, fluid levels in each of a hot and cold reservoir coupled to the temperature controlled component are maintained in part by a passive leveling pipe coupling the two reservoirs. In another embodiment, digital heat transfer fluid flow control valves are opened with pulse widths dependent on a heating/cooling duty cycle value and a proportioning cycle having a duration that has been found to provide good temperature control performance.

主权项

1. A plasma processing apparatus, comprising:
a process chamber including a chuck configured to support the workpiece during processing; a first heat transfer fluid reservoir at a first temperature; a second heat transfer fluid reservoir at a second temperature; a first supply line and a first return line coupling both the first and second heat transfer fluid reservoirs to the chuck for conducting heat transfer fluid at the first or second temperature to the chuck; a first valve coupling the first heat transfer fluid reservoir with the first supply line and a second valve coupling the second heat transfer fluid reservoir with the first supply line; and a passive leveling pipe coupling the first heat transfer fluid reservoir to the second heat transfer fluid reservoir to equalize heat transfer fluid levels by gravity.