Ion beam etching machine and lower electrode structure thereof

The present application discloses an ion beam etching machine and a lower electrode structure thereof. The lower electrode structure includes an electrode plate, a pressing ring mechanism and a lifting mechanism. The pressing ring mechanism is used to support the part to be etched. The lifting mechanism is used to drive the pressing ring mechanism to lift relative to the electrode plate. A position detection mechanism is further included. The position detection mechanism is used for detecting the descending position of the pressing ring mechanism relative to the electrode plate, and the lifting mechanism is used to stop driving the pressing ring mechanism to descend according to the detection information fed back by the position detection mechanism. The arrangement of the lower electrode structure can avoid the fragments of the to-be-etched part and improve the product yield.