A microelectronic device includes a die with input/output (I/O) terminals, and a dielectric layer on the die. The microelectronic device includes electrically conductive pillars which are electrically coupled to the I/O terminals, and extend through the dielectric layer to an exterior of the microelectronic device. Each pillar includes a column electrically coupled to one of the I/O terminals, and a head contacting the column at an opposite end of the column from the I/O terminal. The head extends laterally past the column in at least one lateral direction. Methods of forming the pillars and the dielectric layer are disclosed.

A microelectronic device has a bump bond structure including an electrically conductive pillar with an expanded head, and solder on the expanded head. The electrically conductive pillar includes a column extending from an I/O pad to the expanded head. The expanded head extends laterally past the column on at least one side of the electrically conductive pillar. In one aspect, the expanded head may have a rounded side profile with a radius approximately equal to a thickness of the expanded head, and a flat top surface. In another aspect, the expanded head may extend past the column by different lateral distances in different lateral directions. In a further aspect, the expanded head may have two connection areas for making electrical connections to two separate nodes. Methods for forming the microelectronic device are disclosed.

In one instance, a method of forming a semiconductor package with a leadframe includes cutting, such as with a laser, a first side of a metal strip to a depth D1 according to a cutting pattern to form a first plurality of openings, which may be curvilinear. The method further includes etching the second side of the metal strip to a depth D2 according to a photoresist pattern to form a second plurality of openings. At least some of the first plurality of openings are in fluid communication with at least some of the second plurality of openings to form a plurality of leadframe leads. The depth D1 is shallower than a height H of the metal strip, and the depth D2 is also shallower than the height H. Other embodiments are presented.

In one instance, a semiconductor package includes a metal leadframe having a first plurality of openings extending partially into the leadframe from the first side and a second plurality of openings extending partially into the leadframe from the second side together forming a plurality of leads. A pre-mold compound is positioned in the second plurality of openings that at least partially supports the plurality of leads. The seminconductor package has a plurality of bumps extending from the landing sites to a semiconductor die and a molding compounding at least partially covering the plurality of bumps and the metal leadframe. Other packages and methods are disclosed.

In one instance, a semiconductor package includes a lead frame and a semiconductor die mounted to the lead frame via a plurality of bumps that are shaped or tapered. Each of the plurality of bumps includes a first end connected to the semiconductor die and an opposing, second end connected to the lead frame. The first end has an end surface area A1. The second end has an end surface area A2. The end surface area A1 of the first end is less than the end surface area A2 of the second end. Other aspects are disclosed.

A cryogenic electronic package includes at least two superconducting and/or conventional metal semiconductor structures. Each of the semiconductor structures includes a substrate and a superconducting trace. Additionally, each of the semiconductor structures includes a passivation layer and one or more under bump metal (UBM) structures. The cryogenic electronic package also includes one or more superconducting and/or conventional metal interconnect structures disposed between selected ones of the at least two superconducting semiconductor structures. The interconnect structures are electrically coupled to respective ones of the UBM structures of the semiconductor structures to form one or more electrical connections between the semiconductor structures. A method of fabricating a cryogenic electronic package is also provided.

Methods and systems for a robust pillar structure for a semiconductor device contacts are disclosed, and may include processing a semiconductor wafer comprising one or more metal pads, wherein the processing may comprise: forming a second metal contact on the one or more metal pads; forming a pillar on the second metal contact, and forming a solder bump on the second metal contact and the pillar, wherein the pillar extends into the solder bump. The second metal contact may comprise a stepped mushroom shaped bump, a sloped mushroom shaped bump, a cylindrical post, and/or a redistribution layer. The semiconductor wafer may comprise silicon. A solder brace layer may be formed around the second metal contact. The second metal contact may be tapered down to a smaller area at the one or more metal pads on the semiconductor wafer. A seed layer may be formed between the second metal contact and the one or more metal pads on the semiconductor wafer. The pillar may comprise copper.

A package structure is provided. The package structure includes a dielectric layer formed over a first substrate and a conductive layer formed in the dielectric layer. The package structure includes an under bump metallurgy (UBM) layer formed over the dielectric layer, and the UBM layer is electrically connected to the conductive layer. The package structure also includes a first protrusion structure formed over the UBM layer, and the first protrusion structure extends upward away from the UBM layer. The package structure further includes a second protrusion structure formed over the UBM layer, and the second protrusion structure extends upward away from the UBM layer. The package structure includes a first conductive connector formed over the first protrusion structure; and a second conductive connector formed over the second protrusion structure. An air gap is formed between the first protrusion structure and the second protrusion structure.

A method of forming a semiconductor device includes: forming an interconnect structure over a substrate; forming a first passivation layer over the interconnect structure; forming a first conductive feature over the first passivation layer and electrically coupled to the interconnect structure; conformally forming a second passivation layer over the first conductive feature and the first passivation layer; forming a dielectric layer over the second passivation layer; and forming a first bump via and a first conductive bump over and electrically coupled to the first conductive feature, where the first bump via is between the first conductive bump and the first conductive feature, where the first bump via extends into the dielectric layer, through the second passivation layer, and contacts the first conductive feature, where the first conductive bump is over the dielectric layer and electrically coupled to the first bump via.

A method of forming a semiconductor device includes: forming an interconnect structure over a substrate; forming a first passivation layer over the interconnect structure; forming a first conductive feature over the first passivation layer and electrically coupled to the interconnect structure; conformally forming a second passivation layer over the first conductive feature and the first passivation layer; forming a dielectric layer over the second passivation layer; and forming a first bump via and a first conductive bump over and electrically coupled to the first conductive feature, where the first bump via is between the first conductive bump and the first conductive feature, where the first bump via extends into the dielectric layer, through the second passivation layer, and contacts the first conductive feature, where the first conductive bump is over the dielectric layer and electrically coupled to the first bump via.