Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

A multi-layer wafer and method of manufacturing such wafer are provided. The method comprises applying at least one stress compensating polymer layer to at least one of two heterogeneous wafers and low temperature bonding the two heterogeneous wafers to bond the stress compensating polymer layer to the other of the two heterogeneous wafers to form a multi-layer wafer pair. The multi-layer wafer comprises two heterogeneous wafers, at least one of the heterogeneous wafers having a stress compensating polymer layer. The two heterogeneous wafers are low temperature bonded together to bond the stress compensating polymer layer to the other of the two heterogeneous wafers.

A package includes a first package component, a second package component over the first package component, and a solder region bonding the first package component to the second package component. At least one ball-height control stud separates the first package component and the second package component from each other, and defines a standoff distance between the first package component and the second package component.

A method includes performing a first strike process to strike a metal bump of a first package component against a metal pad of a second package component. A first one of the metal bump and the metal pad includes copper. A second one of the metal bump and the metal pad includes aluminum. The method further includes performing a second strike process to strike the metal bump against the metal pad. An annealing is performed to bond the metal bump on the metal pad.

In a semiconductor device in which a plurality of semiconductor chips are stacked, performance is enhanced without deteriorating productivity. The semiconductor device has a first semiconductor substrate having a first surface and a second surface opposite the first surface, a first insulating film formed on the first surface, a first hole formed in the first insulating film and partially extending into the first semiconductor substrate, a second hole formed in the second surface, a first electrode entirely filling the first hole, and a conductive film conformally formed in the second hole. The conductive film is electrically connected to a bottom surface of the first electrode and leaves a third hole in the first semiconductor substrate open. The third hole is configured to receive a second electrode of a second semiconductor substrate.

An embodiment of the invention may include a semiconductor structure, and method of forming the semiconductor structure. The semiconductor structure may include a first set of pillars located on a first substrate. The semiconductor structure may include a second set of pillars located on a second substrate. The semiconductor structure may include a joining layer connecting the first pillar to the second pillar. The semiconductor structure may include an underfill layer located between the first and second substrate.

A package includes a first package component, a second package component over the first package component, and a solder region bonding the first package component to the second package component. At least one ball-height control stud separates the first package component and the second package component from each other, and defines a standoff distance between the first package component and the second package component.

An embodiment of the invention may include a semiconductor structure, and method of forming the semiconductor structure. The semiconductor structure may include a first set of pillars located on a first substrate. The semiconductor structure may include a second set of pillars located on a second substrate. The semiconductor structure may include a joining layer connecting the first pillar to the second pillar. The semiconductor structure may include an underfill layer located between the first and second substrate.

An embodiment of the invention may include a semiconductor structure, and method of forming the semiconductor structure. The semiconductor structure may include a first set of pillars located on a first substrate. The semiconductor structure may include a second set of pillars located on a second substrate. The semiconductor structure may include a joining layer connecting the first pillar to the second pillar. The semiconductor structure may include an underfill layer located between the first and second substrate.

An embodiment of the invention may include a semiconductor structure, and method of forming the semiconductor structure. The semiconductor structure may include a first set of pillars located on a first substrate. The semiconductor structure may include a second set of pillars located on a second substrate. The semiconductor structure may include a joining layer connecting the first pillar to the second pillar. The semiconductor structure may include an underfill layer located between the first and second substrate.