An embodiment ladder bump structure includes an under bump metallurgy (UBM) feature supported by a substrate, a copper pillar mounted on the UBM feature, the copper pillar having a tapering curved profile, which has a larger bottom critical dimension (CD) than a top critical dimension (CD) in an embodiment, a metal cap mounted on the copper pillar, and a solder feature mounted on the metal cap.

A semiconductor device includes a substrate, a patterned conductive layer on the substrate, a passivation layer on the substrate and surrounding the patterned conductive layer, a first under bump metallurgy (UBM) and a second UBM on the passivation layer and electrically connected to the patterned conductive layer, and an isolation structure on the passivation layer and between the first UBM and the second UBM.

To improve reliability of a semiconductor device, in a method of manufacturing the semiconductor device, a semiconductor substrate having an insulating film in which an opening that exposes each of a plurality of electrode pads is formed is provided, and a flux member including conductive particles is arranged over each of the electrode pads. Thereafter, a solder ball is arranged over each of the electrode pads via the flux member, and is then heated via the flux member so that the solder ball is bonded to each of the electrode pads. The width of the opening of the insulating film is smaller than the width (diameter) of the solder ball.

An embodiment bump on trace (BOT) structure includes a contact element supported by an integrated circuit, an under bump metallurgy (UBM) feature electrically coupled to the contact element, a metal bump on the under bump metallurgy feature, and a substrate trace on a substrate, the substrate trace coupled to the metal bump through a solder joint and intermetallic compounds, a ratio of a first cross sectional area of the intermetallic compounds to a second cross sectional area of the solder joint greater than forty percent.

A bump structure includes a contact element formed on a substrate and a passivation layer overlying the substrate. The passivation layer includes a passivation opening exposing the contact element. The bump structure also includes a polyimide layer overlying the passivation layer and an under bump metallurgy (UBM) feature electrically coupled to the contact element. The polyimide layer has a polyimide opening exposing the contact element, and the under bump metallurgy feature has a UBM width. The bump structure further includes a copper pillar on the under bump metallurgy feature. A distal end of the copper pillar has a pillar width, and the UBM width is greater than the pillar width.

Wafers include multiple bulk redistribution layers. A terminal contact pad is on a surface of one of the bulk redistribution layers. A final redistribution layer is formed on the surface and in contact with the terminal contact pad. The final redistribution layer is formed from a material other than a material of the plurality of bulk redistribution layers. A solder ball is formed on the terminal contact pad.

Wafers and methods of forming solder balls include etching a hole in a final redistribution layer over a terminal contact pad on a wafer to expose the terminal contact pad. Solder is injected into the hole using an injection nozzle that is in direct contact with the final redistribution layer. The final redistribution layer is etched back. The injected solder is reflowed to form a solder ball.

The disclosure provides a light-emitting device and a displayer. Herein, the light-emitting device includes a substrate, a light-emitting chip, a first light-transmitting layer, a second light-transmitting layer and a nano coating. The light transmittance of the second light-transmitting layer is greater than the light transmittance of the first light-transmitting layer. A reference surface corresponding to the light-emitting chip is arranged above the substrate, and the reference surface is higher than the bottom surface of the light-emitting chip and not higher than the top surface of the light-emitting chip. The first light-transmitting layer covers the surface of the light-emitting chip below the reference surface, and the second light-transmitting layer covers the surface of the light-emitting chip above the reference surface. The nano coating covers the outer surface of the first light-transmitting layer, the outer surface of the second light-transmitting layer and the side surface of the substrate.

A wafer chip-scale package (WCSP) includes a substrate including a semiconductor surface layer including circuitry configured for at least one function having at least a top metal interconnect layer thereon that includes at least one bond pad coupled to a node in the circuitry. A redistribution layer (RDL) including a bump pad is coupled by a trace to metal filled plugs through a passivation layer to the bond pad. A solder ball is on the bump pad, and a dielectric ring is on the bump pad that has an inner area that is in physical contact with the solder ball.

A semiconductor structure may include an insulation layer surrounding side surfaces of vias, connection pads on the vias, respectively, a first insulation member on the insulation layer and including through openings in which the connection pads respectively are disposed, and a second insulation member on the insulation layer and surrounding the first insulation member. Each corresponding connection pad among the plurality of connection pads may be on a corresponding via among the plurality of vias and in a corresponding through opening among the plurality of through openings. A height of the second insulation member may be lower than the heights of the connection pads. Outermost through openings among the through openings may include a first inner side surface defined by a side surface of the first insulation member and a second inner side surface defined by a side surface of the second insulation member.