The invention discloses a method for preparing
copper cylinder salient points. With the adoption of the local
metal seed layer technology and the multilayer sensitive dry film technology, the method includes the steps that a conductive
metal seed layer is prepared on a
dielectric layer; a bonding pad, an outer-layer circuit pattern and an
electroplating lead are prepared on the
metal seed layer; the metal seed layer is etched, a local metal seed layer of a
salient point region where the bonding pad is located is reserved, the portions, except for the
salient point region, of the metal seed layer are all removed, and therefore a first substrate is obtained; a green oil layer is prepared on the first substrate, the portion, in the
salient point region, of the green oil layer is removed, and therefore a second substrate is obtained; multiple
layers of dry films are sequentially prepared on the second substrate, photoetching is then conducted on the dry films on the bonding pad of the salient point region until the bonding pad of the salient point region is exposed,
etching blind holes are formed in the bonding pad, and therefore a third substrate is obtained; the third substrate is electroplated, the
etching blind holes in the bonding pad are plated with
copper, the portions, around the dry films and the bonding pad, of the local metal seed layer are then removed, and therefore
copper cylinder salient points are generated on the bonding pad.