A manufacturing method of a semiconductor structure includes the following steps. A first isolation layer is formed on a first surface of a wafer substrate. A conductive pad is formed on the first isolation layer. A hollow region through the first surface and a second surface of the wafer substrate is formed, such that the first isolation layer is exposed through the hollow region. A laser etching treatment is performed on the first isolation layer that is exposed through the hollow region, such that a first opening is formed in the first isolation layer, and a concave portion exposed through the first opening is formed in the conductive pad.