Embodiments disclosed herein include electronic packages with fin pitch first level interconnects. In an embodiment, the electronic package comprises a die and a package substrate attached to the die by a plurality of first level interconnects (FLIs). In an embodiment, individual ones of the plurality of FLIs comprise, a first pad on the package substrate, a solder on the first pad, a second pad on the die, and a bump on the second pad. In an embodiment, the bump comprises a porous nanostructure, and the solder at least partially fills the porous nanostructure.

An integrated circuit device may include a multi-material toothed bond pad including (a) an array of vertically-extending teeth formed from a first material, e.g., aluminum, and (b) a fill material, e.g., silver, at least partially filling voids between the array of teeth. The teeth may be formed by depositing and etching aluminum or other suitable material, and the fill material may be deposited over the array of teeth and extending down into the voids between the teeth, and etched to expose top surfaces of the teeth. The array of teeth may collectively define an abrasive structure. The multi-material toothed bond pad may be bonded to another bond pad, e.g., using an ultrasonic or thermosonic bonding process, during which the abrasive teeth may abrade, break, or remove unwanted native oxide layers formed on the respective bond pad surfaces, to thereby create a direct and/or eutectic bonding between the bond pads.

A technique for fabricating a bump structure is disclosed. A substrate that includes a set of pads formed on a surface thereof is prepared, in which the pads includes first conductive material. A metallic adhesion layer is coated on each pad. A bump base is formed on each pad by sintering conductive particles using a mold layer, in which the conductive particles includes second conductive material different from the first conductive material.

Even in a case where a pad becomes smaller, solder connection strength is improved. A semiconductor device includes a pad, a diffusion layer, and a melting layer. The pad included by the semiconductor device includes a concave portion on a surface at which solder connection is to be performed. The diffusion layer included by the semiconductor device is disposed at the concave portion and constituted with a metal which remains on the surface of the pad while diffusing into solder upon the solder connection. The melting layer included by the semiconductor device is disposed adjacent to the diffusion layer and constituted with a metal which diffuses and melts into the solder upon the solder connection.

Semiconductor devices having interconnect structures with conductive elements configured to mitigate thermomechanical stresses, and associated systems and methods, are disclosed herein. In one embodiment, a semiconductor package includes a semiconductor die and a pillar structure coupled to the semiconductor die. The pillar structure can include a plurality of conductive elements made of a first conductive material having a first elastic modulus. The pillar structure can further include a continuous region of a second conductive material at least partially surrounding the plurality of conductive elements. The second conductive material can have a second elastic modulus less than the first elastic modulus.

A package comprising a substrate and an integrated device coupled to the substrate through a plurality of pillar interconnects and a plurality of solder interconnects. The plurality of pillar interconnects includes a first pillar interconnect comprising a first cavity. The plurality of solder interconnects comprises a first solder interconnect located in the first cavity of the first pillar interconnect. A planar cross section that extends through the first cavity of the first pillar interconnect may comprise an O shape. The first pillar interconnect comprises a first pillar interconnect portion comprising a first width; and a second pillar interconnect portion comprising a second width that is different than the first width.

Disclosed herein are microelectronic assemblies, as well as related apparatuses and methods. In some embodiments, a microelectronic assembly may include a die having a first conductive contact on a surface; a substrate having a second conductive contact on a surface; and an interconnect electrically coupling the first conductive contact of the die and the second conductive contact of the substrate, wherein the interconnect includes a portion of a nanowire on the second conductive contact and an intermetallic compound (IMC) surrounding at least a portion of the nanowire on the second conductive contact.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

A technique for fabricating bumps on a substrate is disclosed. A substrate that includes a set of pads formed on a surface thereof is prepared. A bump base is formed on each pad of the substrate. Each bump base has a tip extending outwardly from the corresponding pad. A resist layer is patterned on the substrate to have a set of holes through the resist layer. Each hole is aligned with the corresponding pad and having space configured to surround the tip of the bump base formed on the corresponding pad. The set of the holes in the resist layer is filled with conductive material to form a set of bumps on the substrate. The resist layer is stripped from the substrate with leaving the set of the bumps.

Even in a case where a pad becomes smaller, solder connection strength is improved. A semiconductor device includes a pad, a diffusion layer, and a melting layer. The pad included by the semiconductor device includes a concave portion on a surface at which solder connection is to be performed. The diffusion layer included by the semiconductor device is disposed at the concave portion and constituted with a metal which remains on the surface of the pad while diffusing into solder upon the solder connection. The melting layer included by the semiconductor device is disposed adjacent to the diffusion layer and constituted with a metal which diffuses and melts into the solder upon the solder connection.