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.

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.

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.

An electronic assembly and methods of making the assembly are disclosed. The electronic assembly includes a substrate with an elastic member having an intrinsic stress profile. The elastic member has an anchor portion on the surface of the substrate; and a free end biased away from the substrate via the intrinsic stress profile to form an out of plane structure. The substrate includes one or more spacers on the substrate. The electronic assembly includes a chip comprising contact pads. The out of plane structure on the substrate touches corresponding contact pads on the chip, and the spacers on the substrate touch the chip forming a gap between the substrate and the chip.

A method for manufacturing an integrated circuit package includes depositing a first layer of metal at a location of a first metal post that is for connecting an IC die to an external circuit. The method also includes depositing a second layer of metal at the location of the first metal post, and a first layer of metal at a location of a second metal post that is for connecting the IC die to an external circuit.

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 for manufacturing semiconductor devices is provided. A protection layer is conformally deposited over a passivation layer such that the protection layer has a protrusion pattern that protrudes from a top surface of the protection layer. Further, a post-passivation interconnect structure (PPI) is conformally formed on the protection layer such that the PPI structure includes a landing pad region, a protrusion pattern conformal to the protrusion pattern of the protection layer, and a connection line electrically connected to the conductive pad. A solder bump is then placed on the landing pad region in contact with the protrusion pattern of PPI structure. A semiconductor device with bump stop structure is also provided. The protrusion pattern of the PPI structure serves as a bump stop that constrains a ball shift in the placement of the solder bump over the landing pad.

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.