External electrical connectors and methods of forming such external electrical connectors are discussed. A method includes forming an external electrical connector structure on a substrate. The forming the external electrical connector structure includes plating a pillar on the substrate at a first agitation level affected at the substrate in a first solution. The method further includes plating solder on the external electrical connector structure at a second agitation level affected at the substrate in a second solution. The second agitation level affected at the substrate is greater than the first agitation level affected at the substrate. The plating the solder further forms a shell on a sidewall of the external electrical connector structure.

A method and apparatus for performing metal-to-metal bonding for an electrical device and an electrical device produced thereby. For example and without limitation, various aspects of this disclosure provide a process that comprises depositing a thin metal layer on a copper pillar and then mating the copper pillar with another copper element. Atoms of the thin metal layer may, for example, form a substitutional solid solution or intermetallic compounds with copper. A concentration gradient is introduced by the thin metal layer, and diffusion at the CuCu interface begins immediately. The thin metal film and the copper may, for example, diffuse until the interface disappears or substantially disappears.

An electronic device includes a semiconductor die having a first side, an orthogonal second side for mounting to a substrate or circuit board, a conductive terminal on the first side, the conductive terminal having a center that is spaced apart from the second side by a first distance along a direction, and a solder structure extending on the conductive terminal, the solder structure having a center that is spaced apart from the center of the conductive terminal by a non-zero second distance along the direction.

The present disclosure relates to a flip-chip package with a hollow-cavity and reinforced interconnects, and a process for making the same. The disclosed flip-chip package includes a substrate, a reinforcement layer over an upper surface of the substrate, a flip-chip die attached to the upper surface of the substrate by interconnects through the reinforcement layer, an air cavity formed between the substrate and the flip-chip die, and a protective layer encapsulating the flip-chip die and defining a perimeter of the air cavity. Herein, a first portion of each interconnect is encapsulated by the reinforcement layer and a second portion of each interconnect is exposed to the air cavity. The reinforcement layer provides reinforcement to each interconnect.

A method and apparatus for performing metal-to-metal bonding for an electrical device and an electrical device produced thereby. For example and without limitation, various aspects of this disclosure provide a process that comprises depositing a thin metal layer on a copper pillar and then mating the copper pillar with another copper element. Atoms of the thin metal layer may, for example, form a substitutional solid solution or intermetallic compounds with copper. A concentration gradient is introduced by the thin metal layer, and diffusion at the Cu-Cu interface begins immediately. The thin metal film and the copper may, for example, diffuse until the interface disappears or substantially disappears.

External electrical connectors and methods of forming such external electrical connectors are discussed. A method includes forming an external electrical connector structure on a substrate. The forming the external electrical connector structure includes plating a pillar on the substrate at a first agitation level affected at the substrate in a first solution. The method further includes plating solder on the external electrical connector structure at a second agitation level affected at the substrate in a second solution. The second agitation level affected at the substrate is greater than the first agitation level affected at the substrate. The plating the solder further forms a shell on a sidewall of the external electrical connector structure.

An electronic device and a method of making an electronic device. As non-limiting examples, various aspects of this disclosure provide various methods of making electronic devices, and electronic devices made thereby, that utilize a film assist mold process.

A microelectronic package can include a substrate having a first surface and a second surface opposite therefrom, the substrate having a first conductive element at the first surface, and a plurality of wire bonds, each of the wire bonds having a base electrically connected to a corresponding one of the first conductive elements and having a tip remote from the base, each wire bond having edge surfaces extending from the tip toward the base. The microelectronic package can also include an encapsulation having a major surface facing away from the first surface of the substrate, the encapsulation having a recess extending from the major surface in a direction toward the first surface of the substrate, the tip of a first one of the wire bonds being disposed within the recess, and an electrically conductive layer overlying an inner surface of the encapsulation exposed within the recess, the electrically conductive layer overlying and electrically connected with the tip of the first one of the wire bonds.

The present disclosure relates to a flip-chip package with a hollow-cavity and reinforced interconnects, and a process for making the same. The disclosed flip-chip package includes a substrate, a reinforcement layer over an upper surface of the substrate, a flip-chip die attached to the upper surface of the substrate by interconnects through the reinforcement layer, an air cavity formed between the substrate and the flip-chip die, and a protective layer encapsulating the flip-chip die and defining a perimeter of the air cavity. Herein, a first portion of each interconnect is encapsulated by the reinforcement layer and a second portion of each interconnect is exposed to the air cavity. The reinforcement layer provides reinforcement to each interconnect.

A method of forming an integrated circuit device includes forming a mask layer overlying an under bump metallurgy (UBM) layer, wherein the mask layer comprises a first portion adjacent to the UBM layer, and a second portion overlying the first portion. The method further includes forming an opening in the mask layer to expose a portion of the UBM layer. The method further includes forming a conductive layer in the opening of the mask layer, electrically connected to the exposed portion of the UBM layer. The method further includes removing the second portion of the mask layer to expose an upper portion of the conductive layer. The method further includes forming a barrier layer on the exposed upper portion of the conductive layer.