Abstract: An ion beam etching machine and a lower electrode structure thereof. The lower electrode structure comprises an electrode plate, a ring pressing mechanism, and a lifting mechanism, the ring pressing mechanism being configured to support a member to be etched, and the lifting mechanism being configured to drive the ring pressing mechanism to ascend and descend relative to the electrode plate; and same further comprises a position measurement mechanism for measuring a position to which the ring pressing mechanism descends relative to the electrode plate. The lifting mechanism is configured to stop driving the ring pressing mechanism to descend based on measurement information fed back by the position measurement mechanism. The arrangement of the lower electrode structure can avoid fragmenting of the member to be etched, and improve the product yield.

Abstract: Disclosed in the present disclosure is a double-deck multi-span bridge construction method. According to the double-deck bridge construction method of the present disclosure, construction is carried out by using a method of disassembling a support jig frame in a graded and span-separated mode, an upper chord jig frame and a lower chord jig frame can be used in a recycle manner, and construction costs are reduced. In addition, a construction period of building the support jig frame is shortened, and other construction operations can be synchronously carried out on a span in which the jig frame is disassembled, for example, fire retardant coating construction can be carried out on a mounted bridge deck after the jig frame is disassembled, and the construction period of a double-deck multi-span bridge is effectively shortened.

Abstract: A substrate supporting apparatus includes a rotatable chuck, a first mass flow controller, a second mass flow controller, a plurality of locating pins and guiding pillars, and a motor in which the rotatable chuck defines a plurality of first injecting ports and second injecting ports, the first injecting ports are connected with a first gas passage for supplying gas to the substrate and sucking the substrate by Bernoulli effect, the second injecting ports are connected with a second gas passage for supplying gas to the substrate and lifting the substrate, the first and the second mass flow controllers are respectively installed on the first and the second gas passages, the plurality of locating pins and guiding pillars are disposed at the top surface of the rotatable chuck and every guiding pillar protrudes to form a holding portion, and the motor is used for rotating the rotatable chuck.

Abstract: A substrate supporting apparatus includes a rotatable chuck, a first mass flow controller, a second mass flow controller, a plurality of locating pins and guiding pillars, and a motor in which the rotatable chuck defines a plurality of first injecting ports and second injecting ports, the first injecting ports are connected with a first gas passage for supplying gas to the substrate and sucking the substrate by Bernoulli effect, the second injecting ports are connected with a second gas passage for supplying gas to the substrate and lifting the substrate, the first and the second mass flow controllers are respectively installed on the first and the second gas passages, the plurality of locating pins and guiding pillars are disposed at the top surface of the rotatable chuck and every guiding pillar protrudes to form a holding portion, and the motor is used for rotating the rotatable chuck.