The invention relates to the technical field of
metal etching solutions, in particular to an
etching solution as well as a preparation method and an
etching method thereof. The etching liquid comprises the following components in percentage by
mass: 5 to 10 weight percent of
hydrogen peroxide, 4 to 6 weight percent of
nitric acid, 0.1 to 5 weight percent of
hydrogen peroxide stabilizer, 0.1 to 5 weight percent of
metal ion chelating agent, 0.01 to 5 weight percent of
metal corrosion inhibitor, 0.3 to 0.5 weight percent of chlorinated diphenyl iodonium and the balance of water. In the etching solution, the content of
hydrogen peroxide is low, and
fluorine ions are not contained; the etching liquid has the advantages of being high in safety, good in stability, excellent in etching performance, capable of meeting the high-precision
machining requirement and the like. When the etching solution is used for etching an etched sheet containing a
copper-
titanium metal film, uniform etching can be realized, the CD bias variation is less than 0.1 mu m, the etching CD and the
slope angle are basically unchanged, and no surface metal residue and no
titanium residue phenomenon exist.