A semiconductor structure includes a solder resist layer disposed on a circuit substrate and partially covering contact pads of the circuit substrate, and external terminals disposed on the solder resist layer and extending through the solder resist layer to land on the contact pads. The external terminals include a first external terminal and a second external terminal which have different heights. A first interface between the first external terminal and corresponding one of the contact pads underlying the first external terminal is less than a second interface between the second external terminal and another corresponding one of the contact pads underlying the second external terminal.