Semiconductor device and method of forming same

A method comprising:

• forming an interconnect structure over a substrate, the substrate comprising an active device, the interconnect structure comprising a plurality of metal layers and vias in a plurality of dielectric layers, the plurality of metal layers and vias comprising:
• a first portion of the plurality of metal layers and vias electrically coupled to the active device;
• and
• a second portion of the plurality of metal layers and vias along a periphery of the substrate;
• forming a first redistribution layer, a second redistribution layer, and a third redistribution layer over the interconnect structure, the first redistribution layer physically contacting the first portion of the plurality of metal layers and vias, the second redistribution layer physically contacting the second portion of the plurality of metal layers and vias, the third redistribution layer physically contacting the second portion of the plurality of metal layers and vias, the second redistribution layer being spaced apart from the third redistribution layer by a first spacing, the second portion of the plurality of metal layers and vias and the second and third redistribution layers being part of a seal ring structure, the second and third redistribution layers being in a top conductive layer of the seal ring structure that is furthest from the substrate;
• and
• forming a polymer layer over the first, second, and third redistribution layers, the polymer layer covering the first and the third redistribution layers and partially covering the second redistribution layer, the polymer layer having an outermost edge that is over and laterally within bounds of a top surface of the second redistribution layer, the polymer layer having a non-uniform thickness over the first, second, and third redistribution layers and the interconnect structure, the polymer layer having a planar top surface over the first, second, and third redistribution layers and the interconnect structure.

A method comprising:

• forming an interconnect structure over a substrate, the substrate comprising an active device, wherein forming the interconnect structure comprises forming a plurality of metal layers and vias in a plurality of dielectric layers, the plurality of metal layers and vias comprising a first portion of the plurality of metal layers and vias electrically coupled to the active device, and a second portion of the plurality of metal layers and vias along a periphery of the substrate;
• conformally depositing a first passivation layer over the interconnect structure;
• forming a first redistribution layer, a second redistribution layer, and a third redistribution layer over the interconnect structure and the first passivation layer, each of the first redistribution layer, the second redistribution layer, and the third redistribution layer extending through the first passivation layer, the first redistribution layer physically contacting the first portion of the plurality of metal layers and vias, the second redistribution layer physically contacting the second portion of the plurality of metal layers and vias, the third redistribution layer physically contacting the second portion of the plurality of metal layers and vias, the second redistribution layer being spaced apart from the third redistribution layer by a first spacing, the second redistribution layer having a first sidewall and a second sidewall, the first sidewall facing the first redistribution layer, the second sidewall facing away from the first redistribution layer;
• and
• conformally depositing a second passivation layer over the first redistribution layer, the second redistribution layer, and the third redistribution layer;
• forming a polymer layer over the second passivation layer, the polymer layer having an outer edge that is over a top surface of the second redistribution layer and between the first and second sidewalls of the second redistribution layer, the polymer layer having a planar top surface extending from over the second redistribution layer to over the third redistribution layer;
• forming a conductive connector on the polymer layer, the conductive connector extending through the polymer layer and the second passivation layer and being electrically coupled to the first redistribution layer, the second and third redistribution layers being free from overlying conductive connectors;
• and
• bonding a second substrate to the conductive connector, wherein after bonding the second substrate to the conductive connector, the polymer layer covers the third redistribution layer.