Embodiments of mechanisms for forming a package structure are provided. The package structure includes a semiconductor die and a substrate. The package structure includes a pillar bump and an elongated solder bump bonded to the semiconductor die and the substrate. A height of the elongated solder bump is substantially equal to a height of the pillar bump. The elongated solder bump has a first width, at a first horizontal plane passing through an upper end of a sidewall surface of the elongated solder bump, and a second width, at a second horizontal plane passing through a midpoint of the sidewall surface. A ratio of the second width to the first width is in a range from about 0.5 to about 1.1.

A method includes placing a first package component and a second package component over a carrier. The first conductive pillars of the first package component and second conductive pillars of the second package component face the carrier. The method further includes encapsulating the first package component and the second package component in an encapsulating material, de-bonding the first package component and the second package component from the carrier, planarizing the first conductive pillars, the second conductive pillars, and the encapsulating material, and forming redistribution lines to electrically couple to the first conductive pillars and the second conductive pillars.

Conventional packages for 5G applications suffer from disadvantages including high mold stress on the die, reduced performance, and increased keep-out zone. To address these and other issues of the conventional packages, it is proposed to pre-apply a wafer-applied material, which remains in place, to form an air cavity between the die and the substrate. The air cavity can enhance the die's performance. Also, since the wafer-applied material can remain in place, the keep-out zone can be reduced. As a result, higher density modules can be fabricated.

A method for manufacturing a semiconductor device including a plurality of semiconductor chips includes steps of placing, on a first semiconductor chip, a second semiconductor chip, such that a plurality of bumps is located between the first semiconductor chip and the second semiconductor chip, determining a distance between the first semiconductor chip and the second semiconductor chip, and determining whether or not the distance is within a predetermined range and stopping placement of additional chips if the distance is determined to be outside the predetermined range.

A wafer-level semiconductor die attachment method includes placing a semiconductor die of a plurality of semiconductor dies at an initial placement position to overlap a sub-mount pad on a sub-mount of a pre-singulated wafer. A die pad of the semiconductor die comes in contact with a solder layer deposited over the sub-mount pad. The semiconductor die and the sub-mount include a plurality of die and sub-mount mating features, respectively. The solder layer is heated locally to temporarily hold the semiconductor die at the initial placement position. The pre-singulated wafer is reflowed, when each semiconductor die is temporarily held at the corresponding initial placement position. During reflow, each semiconductor die slides from the initial placement position and a contact is established between the corresponding plurality of die and sub-mount mating features. Thereby, each semiconductor die is permanently attached to the corresponding sub-mount.

Embodiments of mechanisms for forming a package structure are provided. The package structure includes a semiconductor die and a substrate. The package structure includes a pillar bump and an elongated solder bump bonded to the semiconductor die and the substrate. A height of the elongated solder bump is substantially equal to a height of the pillar bump. The elongated solder bump has a first width, at a first horizontal plane passing through an upper end of a sidewall surface of the elongated solder bump, and a second width, at a second horizontal plane passing through a midpoint of the sidewall surface. A ratio of the second width to the first width is in a range from about 0.5 to about 1.1.

An integrated circuit structure includes a substrate, a metal pad over the substrate, a passivation layer having a portion over the metal pad, and a polymer layer over the passivation layer. A Post-Passivation Interconnect (PPI) has a portion over the polymer layer, wherein the PPI is electrically coupled to the metal pad. The integrated circuit structure further includes a first solder region over and electrically coupled to a portion of the PPI, a second solder region neighboring the first solder region, a first coating material on a surface of the first solder region, and a second coating material on a surface of the second solder region. The first coating material and the second coating material encircle the first solder region and the second solder region, respectively. The first coating material is spaced apart from the second coating material.

A method for forming a semiconductor structure includes: providing a semiconductor substrate having a first pad and a second pad on a top surface of the semiconductor substrate; providing a circuit board having an active pad and a non-metallic surface; providing a first solder ball and a second solder ball on the active pad and the non-metallic surface respectively; attaching the first pad and the second pad on the first solder ball and the second solder ball respectively; and reflowing the first solder ball and the second solder ball to form a first bump wetted on the active pad and a second bump not wetted on the non-metallic surface.

A laminated semiconductor device includes: three or more semiconductor chips that are laminated; resins that are disposed among the semiconductor chips, the resins softening by heating; and support members that are disposed among the semiconductor chips and that contacts the adjacent semiconductor chips, the support members deforming by external force when a temperature of the support members reaching a predetermined temperature.

A semiconductor device has a semiconductor die with an insulation layer formed over an active surface of the semiconductor die. A conductive layer is formed over the first insulating layer electrically connected to the active surface. A plurality of conductive pillars is formed over the conductive layer. A plurality of dummy pillars is formed over the first insulating layer electrically isolated from the conductive layer and conductive pillars. The semiconductor die is mounted to a substrate. A height of the dummy pillars is greater than a height of the conductive pillars to maintain the standoff distance between the semiconductor die and substrate. The dummy pillars can be formed over the substrate. The dummy pillars are disposed at corners of the semiconductor die and a central region of the semiconductor die. A mold underfill material is deposited between the semiconductor die and substrate.