The invention discloses a fine high-efficiency
etching technology in a high-order high-density circuit board. The technology has the following steps that S1)
copper plates are welded to the top and bottom of a substrate respectively,
adhesive tapes are pasted to the top of the upper
copper plate and the bottom of the lower
copper plate respectively, the shapes of the
adhesive tapes are kept consistent with that of a required line layer, sealing strips are pasted to positions where the
adhesive tapes make contact with the substrate, an
etching solution is avoided from corroding copper materialsunder the adhesive tapes, and accurate
etching is achieved; and S2) an etching
machine is prepared by that a rotating shaft is installed at the two sides of an etching groove rotationally, one end ofthe rotating shaft is provided with a handwheel, a bearing table is welded to the rotating shaft, two blind holes are formed in the top of the bearing table, extension springs are welded into the blind holes respectively, a pressure plate is welded to the top of each spring, and an outlet duct is connected to a gas outlet of an
air compressor. Thus, the etching cost can be reduced, inorganic acidcan be used in a cyclic way, and operation is simple.