A semiconductor structure and a manufacturing method thereof are disclosed. The semiconductor structure includes a semiconductor substrate, a metal pad, a bump, a metal barrier layer, and a solder layer. The metal pad is arranged on the semiconductor substrate; the bump is arranged on the metal pad; the metal barrier layer is arranged on the side of the bump away from the metal pad; the metal barrier layer contains a storage cavity; the sidewall of the metal barrier layer is configured with an opening connecting to the storage cavity; the solder layer is arranged inside the storage cavity, and the top side of the solder layer protrudes from the upper side of storage cavity. During the flip-chip soldering process, solder is heated to overflow, the opening allows the solder flow out through the opening. The openings achieve good solder diversion in overflow, thus mitigating the problem of solder bridging between bumps.