Manufacturing method of a bump structure having a reinforcement member

A manufacturing method of a bump structure having a reinforcement member, comprising:

• providing a substrate comprising a plurality of pads and a passivation layer, wherein the passivation layer has a plurality of first openings, each of the first openings respectively exposing a portion of the corresponding pad;
• forming an under ball metal material layer on the substrate to cover the passivation layer and the pads exposed by the passivation layer;
• forming a plurality of bumps on the under ball metal material layer on the pads exposed by the passivation layer, wherein a lower surface of each of the bumps is smaller than a lower surface of each of the corresponding first openings, and an upper surface of each of the bumps is planar;
• forming a reinforcement member on the under ball metal material layer around each of the bumps, wherein each of the reinforcement members contacts with each of the bumps, a portion of the reinforcement member is located in each of the first openings, edges of the reinforcement member are aligned with edges of the under ball metal layers, a top surface of each of the reinforcement members is lower than a top surface of each of the bumps, and the material of the reinforcement member is a polymer;
• and
• patterning the under ball metal material layer to form a plurality of under ball metal layers, wherein a lower surface of each of the under ball metal layers is larger than the lower surface of each of the corresponding first openings.