A method of forming a semiconductor package is provided. The method includes forming a metallization stack over a semiconductor die. Polymer particles are mounted over the metallization stack. Each of the polymer particles is coated with a first bonding layer. A heat spreader lid is bonded with the semiconductor die by reflowing the first bonding layer. A composite thermal interface material (TIM) structure is formed between the heat spreader lid and the semiconductor die during the bonding. The composite TIM structure includes the first bonding layer and the polymer particles embedded in the first bonding layer.

A method of forming a semiconductor package is provided. The method includes forming a metallization stack over a semiconductor die. Polymer particles are mounted over the metallization stack. Each of the polymer particles is coated with a first bonding layer. A heat spreader lid is bonded with the semiconductor die by reflowing the first bonding layer. A composite thermal interface material (TIM) structure is formed between the heat spreader lid and the semiconductor die during the bonding. The composite TIM structure includes the first bonding layer and the polymer particles embedded in the first bonding layer.

A semiconductor package may include a base, a first chip on the base, and first connection patterns that connect and couple the base and the first chip. The first chip may include a substrate, pad patterns on the substrate, a passivation layer on the substrate and having openings, and pillars on the substrate, the pad patterns include a first signal pad and a second signal pad, the first connection patterns are in contact with the pillars, the pillars include a first signal pillar in contact with the first signal pad and a second signal pillar in contact with the second signal pad, the openings in the passivation layer include a first opening having a sidewall facing a side surface of the first signal pillar and surrounding the side surface of the first signal pillar, and a second opening having a sidewall facing a side surface of the second signal pillar and surrounding the side surface of the second signal pillar, and a maximum width of the second opening is greater than a maximum width of the first opening.

A semiconductor device that includes a bipolar transistor, wherein a third opening, through which a pillar bump and a second wiring line, which is electrically connected to an emitter layer, contact each other, is shifted in a longitudinal direction of the emitter layer away from a position at which the third opening would be directly above the emitter layer. The third opening is arranged, with respect to the emitter layer, such that an end portion of the emitter layer in the longitudinal direction of the emitter layer and the edge of the opening of the third opening are substantially aligned with each other.

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.

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.

One or more implementations of the subject technology may enable a bond-on-pad (BoP) substrate technology that can eliminate the need to utilize a solder-on-pad (SoP) process. Unlike an SoP process, a BoP Process does not require a solder bump to be formed on a bump pad to attach a joint to a bump pad. The size of an opening on a bump pad for a BoP process may be larger than that of an SoP process. A BoP process may use a solder mask having multiple thicknesses and may be thinner near the bump pads. A BoP process may use a joint having a copper pillar and a solder cap. A BoP process can be used with an underfill or a molding compound technology.

A semiconductor device includes a substrate having a plurality of pads on a surface of the substrate, a semiconductor chip that includes a plurality of metal bumps connected to corresponding pads on the substrate, a first resin layer between the surface of the substrate and the semiconductor chip, a second resin layer between the substrate and the semiconductor chip and between the first resin layer and at least one of the metal bumps, and a third resin layer on the substrate and above the semiconductor chip.

A method for fabricating a semiconductor structure is provided. The method includes: providing a semiconductor chip comprising an active surface; forming a conductive bump over the active surface of the semiconductor chip; and coupling the conductive bump to a substrate. The conductive bump includes a plurality of bump segments including a first group of bump segments and a second group of bump segments. Each bump segment has a same segment thickness in a direction orthogonal to the active surface of the semiconductor chip, and each bump segment has a volume defined by a multiplication of the same segment thickness with an average cross-sectional area of the bump segment in a plane parallel to the active surface of the semiconductor chip. A ratio of a total volume of the first group of bump segments to a total volume of the second group of bump segments is between 0.03 and 0.8.

A method for fabricating a semiconductor structure is provided. The method includes: providing a semiconductor chip comprising an active surface; forming a conductive bump over the active surface of the semiconductor chip; and coupling the conductive bump to a substrate. The conductive bump includes a plurality of bump segments including a first group of bump segments and a second group of bump segments. Each bump segment has a same segment thickness in a direction orthogonal to the active surface of the semiconductor chip, and each bump segment has a volume defined by a multiplication of the same segment thickness with an average cross-sectional area of the bump segment in a plane parallel to the active surface of the semiconductor chip. A ratio of a total volume of the first group of bump segments to a total volume of the second group of bump segments is between 0.03 and 0.8.