Bump structure and method of manufacturing bump structure

A method of manufacturing a semiconductor device, comprising:

• forming a first passivation layer over a substrate;
• forming an opening in the first passivation layer;
• forming a metal pad structure in the opening;
• forming a second passivation layer over the metal pad structure,
• wherein the first passivation layer and the second passivation layer are formed of different materials;
• forming an opening in the second passivation layer over the metal pad structure exposing a portion of the metal pad structure;
• forming a polyimide layer comprising a polyimide over the second passivation layer and the metal pad structure;
• and
• forming a metal bump over the metal pad structure and the polyimide layer, wherein the polyimide is a reaction product of a dianhydride and a diamine, wherein at least one of the dianhydride and the diamine comprises one selected from the group consisting of a cycloalkane, a fused ring, a bicycloalkane, a tricycloalkane, a bicycloalkene, a tricycloalkene, a spiroalkane, and a heterocyclic ring.

A semiconductor device, comprising:

• a chip bonded to a chip carrying substrate;
• a passivation layer disposed over a main side of the chip facing the chip carrying substrate,
• wherein the passivation layer surrounds a first metal pad;
• a polyimide layer including a polyimide disposed over the passivation layer and the first metal pad;
• and
• a metal bump disposed over the first metal pad and the polyimide layer,
• wherein the metal bump is in electrical contact with the first metal pad and a second metal pad on the chip carrying substrate, and
• wherein the polyimide is a reaction product of a dianhydride and a diamine, wherein at least one of the dianhydride and the diamine comprises one selected from the group consisting of a cycloalkane, a fused ring, a bicycloalkane, a tricycloalkane, a bicycloalkene, a tricycloalkene, a spiroalkane, and a heterocyclic ring.