| Supercritical dryThe supercritical release system dries wafers or dies after wet processing (such as release) without any surface tension (thus preventing stiction). The supercritical CO2 release system uses liquid CO2 to displace methanol from the system chamber at pressure. The chamber is then heated past the CO2 supercritical point, and the pressure released. The supercritical CO2 has extremely low surface tension, and as a result does not pull structures down as it transitions from liquid to gas. It is also an excellent cleaning fluid as the supercritical state retains the ability of liquid CO2 to dissolve organic compounds and oils, while the lowered surface tension makes it easier for the fluid to penetrate complex geometries and small cracks.
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