One aspect of the present invention is directed to an apparatus for cryogenically cooling a substance. The apparatus of the present invention includes a thin film evaporator comprising a microstructured surface and an applicator for dispensing a working fluid onto the microstructured surface. The apparatus preferably contains a pressure-controlled vessel enclosing the thin film evaporator and at least a portion of the applicator. In a second aspect, the present invention is directed to the method of using a thin film evaporator of the present invention to cryogenically cool a substance by forming a thin film layer of the working fluid on the microstructured surface of the thin film evaporator.
