Low stress bumps can be used to reduce stress and strain on bumps bonded to a substrate with different coefficients of thermal expansion (CTEs) from the die. The low stress bumps include multiple polymer layers. More than one type of bump is coupled to a die, with low stress bumps placed on areas subjected to high stress.

A semiconductor structure includes a substrate; a pad disposed over the substrate; a passivation disposed over the substrate and exposing a portion of the pad; and a bump disposed over the portion of the pad. The bump includes a buffering member disposed over the portion of the pad; and a conductive layer surrounding the buffering member and electrically connected to the pad.

A semiconductor structure includes a substrate; a pad disposed over the substrate; a passivation disposed over the substrate and exposing a portion of the pad; and a bump disposed over the portion of the pad. The bump includes a buffering member disposed over the portion of the pad; and a conductive layer surrounding the buffering member and electrically connected to the pad.

A method for producing a stack of semiconductor devices and the stacked device obtained thereof are disclosed. In one aspect, the method includes providing a first semiconductor device comprising a dielectric layer with a hole, the hole lined with a metal layer and partially filled with solder material. The method also includes providing a second semiconductor device with a compliant layer having a metal protrusion through the compliant layer, the protrusion capped with a capping layer. The method further includes mounting the devices by landing the metal protrusion in the hole, where the compliant layer is spaced from the dielectric layer. The method includes thereafter reflowing the solder material, thereby bonding the devices such that the compliant layer is contacting the dielectric layer.

A method for producing a stack of semiconductor devices and the stacked device obtained thereof are disclosed. In one aspect, the method includes providing a first semiconductor device comprising a dielectric layer with a hole, the hole lined with a metal layer and partially filled with solder material. The method also includes providing a second semiconductor device with a compliant layer having a metal protrusion through the compliant layer, the protrusion capped with a capping layer. The method further includes mounting the devices by landing the metal protrusion in the hole, where the compliant layer is spaced from the dielectric layer. The method includes thereafter reflowing the solder material, thereby bonding the devices such that the compliant layer is contacting the dielectric layer.

Semiconductor packages include a first substrate including a central portion and a peripheral portion, at least one first central connection member attached to the central portion of the first substrate, and at least one first peripheral connection member attached to the peripheral portion of the first substrate. The first central connection member includes a first supporter and a first fusion conductive layer surrounding the first supporter.

Semiconductor packages include a first substrate including a central portion and a peripheral portion, at least one first central connection member attached to the central portion of the first substrate, and at least one first peripheral connection member attached to the peripheral portion of the first substrate. The first central connection member includes a first supporter and a first fusion conductive layer surrounding the first supporter.

A method forming an interconnect structure includes depositing a first solder bump on a chip; depositing a second solder bump on a laminate, the second solder bump including a nickel copper colloid surrounded by a nickel or copper shell and suspended in a tin-based solder; aligning the chip with the laminate; performing a first reflow process to join the chip to the laminate; depositing an underfill material around the first solder bump and the second solder bump; and performing a second reflow process at a temperature that is lower than the first reflow process to convert the first solder bump and the second solder bump to an all intermetallic interconnect; wherein depositing the underfill material is performed before or after performing the second reflow process.

A method forming an interconnect structure includes depositing a first solder bump on a chip; depositing a second solder bump on a laminate, the second solder bump including a nickel copper colloid surrounded by a nickel or copper shell and suspended in a tin-based solder; aligning the chip with the laminate; performing a first reflow process to join the chip to the laminate; depositing an underfill material around the first solder bump and the second solder bump; and performing a second reflow process at a temperature that is lower than the first reflow process to convert the first solder bump and the second solder bump to an all intermetallic interconnect; wherein depositing the underfill material is performed before or after performing the second reflow process.

Interconnect structures with intermetallic palladium joints are disclosed herein. In one embodiment, a method of forming an interconnect structure includes depositing a first conductive material comprising nickel on a first conductive surface of a first die, and depositing a second conductive material comprising nickel on a second conductive surface of a second die spaced apart from the first surface. The method further includes depositing a third conductive material on the second conductive material, and thermally compressing tin/solder between the first and third conductive materials to form an intermetallic palladium joint that extends between the first conductive material and the second conductive material such that one end of the intermetallic palladium joint is bonded directly to the first conductive material and an opposite end of the intermetallic palladium joint is bonded directly to the second conductive material.