The present disclosure is directed to a wafer level chip scale package (WLCSP) with various combinations of contacts and Under Bump Metallizations (UBMs) having different structures and different amounts solder coupled to the contacts and UBMs. Although the contacts have different structures and the volume of solder differs, the total standoff height along the WLCSP remains substantially the same. Each portion of solder coupled to each respective contact and UBM includes a point furthest away from an active surface of a die of the WLCSP. Each point of each respective portion of solder is co-planar with each other respective point of the other respective portions of solder. Additionally, the contacts with various and different structures are positioned accordingly on the active surface of the die of the WLCSP.

The present disclosure is directed to a wafer level chip scale package (WLCSP) with various combinations of contacts and Under Bump Metallizations (UBMs) having different structures and different amounts solder coupled to the contacts and UBMs. Although the contacts have different structures and the volume of solder differs, the total standoff height along the WLCSP remains substantially the same. Each portion of solder coupled to each respective contact and UBM includes a point furthest away from an active surface of a die of the WLCSP. Each point of each respective portion of solder is co-planar with each other respective point of the other respective portions of solder. Additionally, the contacts with various and different structures are positioned accordingly on the active surface of the die of the WLCSP.

Disclosed is a semiconductor device including a conductive pattern on a substrate, a passivation layer on the substrate and including an opening that partially exposes the conductive pattern, and a pad structure in the opening of the passivation layer and connected to the conductive pattern. The pad structure includes a first metal layer that fills the opening of the passivation layer and has a width greater than that of the opening, and a second metal layer on the first metal layer. The first metal layer has a first thickness at an outer wall of the first metal layer, a second thickness on a top surface of the passivation layer, and a third thickness on a top surface of the conductive pattern. The second thickness is greater than the first thickness, and the third thickness is greater than the second thickness.

A semiconductor structure includes a first passivation layer disposed over a metal line, a copper-containing RDL disposed over the first passivation layer, where the copper-containing RDL is electrically coupled to the metal line and where a portion of the copper-containing RDL in contact with a top surface of the first passivation layer forms an acute angle, and a second passivation layer disposed over the copper-containing RDL, where an interface between the second passivation layer and a top surface of the copper-containing RDL is curved. The semiconductor structure may further include a polymeric layer disposed over the second passivation layer, where a portion of the polymeric layer extends to contact the copper-containing RDL, a bump electrically coupled to the copper-containing RDL, and a solder layer disposed over the bump.

A semiconductor structure includes a first passivation layer disposed over a metal line, a copper-containing RDL disposed over the first passivation layer, where the copper-containing RDL is electrically coupled to the metal line and where a portion of the copper-containing RDL in contact with a top surface of the first passivation layer forms an acute angle, and a second passivation layer disposed over the copper-containing RDL, where an interface between the second passivation layer and a top surface of the copper-containing RDL is curved. The semiconductor structure may further include a polymeric layer disposed over the second passivation layer, where a portion of the polymeric layer extends to contact the copper-containing RDL, a bump electrically coupled to the copper-containing RDL, and a solder layer disposed over the bump.

Provided is a method for manufacturing a conductive pillar capable of bonding a substrate and a bonding member with high bonding strength via a bonding layer without employing an electroplating method, and a method for manufacturing a bonded structure by employing this method. A method for manufacturing a conductive pillar 1 includes, in sequence, the steps of forming a resist layer 16 on a substrate 11 provided with an electrode pad 13, the resist layer 16 including an opening portion 16a on the electrode pad 13, forming a thin Cu film 17 by sputtering or evaporating Cu on a surface of the substrate 11 provided with the resist layer 16 including the opening portion 16a, filling the opening portion 16a with a fine particle copper paste 12c, and sintering the fine particle copper paste 12c by heating the substrate 11 filled with the fine particle copper paste 12c.

Methods of coupling inductors in an IC device using interconnecting elements with solder caps and the resulting device are disclosed. Embodiments include forming a top inductor structure, in a top inductor area on a lower surface of a top substrate, the top inductor structure having first and second top terminals at its opposite ends; forming a bottom inductor structure, in a bottom inductor area on an upper surface of a bottom substrate, the bottom inductor structure having first and second bottom terminals at its opposite ends; forming top interconnecting elements on the lower surface of the top substrate around the top inductor area; forming bottom interconnecting elements on the upper surface of the bottom substrate around the bottom inductor area; forming solder bumps on lower and upper surfaces, respectively, of the top and bottom interconnecting elements; and connecting the top and bottom interconnecting elements to each other.

Methods of coupling inductors in an IC device using interconnecting elements with solder caps and the resulting device are disclosed. Embodiments include forming a top inductor structure, in a top inductor area on a lower surface of a top substrate, the top inductor structure having first and second top terminals at its opposite ends; forming a bottom inductor structure, in a bottom inductor area on an upper surface of a bottom substrate, the bottom inductor structure having first and second bottom terminals at its opposite ends; forming top interconnecting elements on the lower surface of the top substrate around the top inductor area; forming bottom interconnecting elements on the upper surface of the bottom substrate around the bottom inductor area; forming solder bumps on lower and upper surfaces, respectively, of the top and bottom interconnecting elements; and connecting the top and bottom interconnecting elements to each other.

Disclosed is a flip-chip device. The flip-chip device includes a die having a plurality of under bump metallizations (UBMs); and a package substrate having a plurality of bond pads. The plurality of UBMs include a first set of UBMs having a first size and a first minimum pitch and a second set of UBMs having a second size and a second minimum pitch. The first set of UBMs and the second set of UBMs are each electrically coupled to the package substrate by a bond-on-pad connection.

A method includes forming a seed layer over a first conductive feature of a wafer, forming a patterned plating mask on the seed layer, and plating a second conductive feature in an opening in the patterned plating mask. The plating includes performing a plurality of plating cycles, with each of the plurality of plating cycles including a first plating process performed using a first plating current density, and a second plating process performed using a second plating current density lower than the first plating current density. The patterned plating mask is then removed, and the seed layer is etched.