Preparation method of deep hole metallization adapter plate

The invention discloses a preparation method of a deep hole metallization adapter plate. The preparation method comprises the following steps: processing a through hole in a substrate; a magnetron sputtering method is adopted to form a first seed layer which continuously and fully covers the upper surface and the lower surface of the substrate; forming a second seed layer which continuously and completely covers the inner wall of the through hole by adopting a chemical plating method; an electroplating method is adopted, and the through holes are filled with electroplating metal; removing the first seed layer on the upper and lower surfaces of the substrate and redundant electroplating metal formed on the upper and lower surfaces of the substrate in the previous step; and performing metal patterning and multiple wiring on the sample obtained in the previous step to obtain the deep hole metallization adapter plate. The preparation method is low in action temperature, low in cost and more suitable for large-sca