Physical vapor deposition machine table and cooling cavity thereof

The invention provides a physical vapor deposition machine table and a cooling cavity thereof. The cooling cavity thereof comprises a cavity body cover, an photoelectric inductor, a lifting ring and a cooling base, wherein the photoelectric inductor is arranged on the cavity cover; the lifting ring is downwards connected with an air cylinder through a lifting arm, and the air cylinder is provided with a lifting position sensor and a release position sensor which are used for judging that the lifting ring is positioned on a lifting position or a release position; a silicon slice is carried on the lifting ring, and the photoelectric inductor is downwards aligned to the silicon slice; and the cooling base is positioned below the silicon slice. The photoelectric inductor emits infrared light beams to the silicon slice, and the infrared light beams are reflected back when meeting with the silicon slice; when the silicon slice is correctly placed on the lifting ring, the infrared light beams which are reflected back can be received by the photoelectric inductor, the photoelectric inductor is switched on, the lifting ring is permitted to carry the silicon slice to descend from the lifting position to the release position; and otherwise, the photoelectric inductor is not switched on, and the machine table stops operating. The physical vapor deposition machine table provided by the invention can be used for automatically detecting whether the position of the silicon slice on the lifting ring inside the cooling cavity is correct or not.