US Patent 10985121 Bump structure and fabricating method thereof

Present disclosure provides a semiconductor structure, including a substrate, a pad on the substrate, a conductive layer electrically coupled to the pad at one end, a metal bump including a top surface and a sidewall, a solder bump on the top surface of the metal bump, a dielectric layer surrounding the sidewall of the metal bump and having a top surface, and the top surface of the metal bump entirely protruding the top surface of the dielectric layer, and a polymer layer on the top surface of the dielectric layer, the polymer layer being spaced from both the sidewall of the metal bump and a nearest outer edge of the solder bump with a gap. A method for fabricating a semiconductor device is also provided.