An electronic device including a solder pad structure and methods of forming an electrical interconnection are shown. Solder pads including one or more projections extending from the pads are shown where the projections occupy only a fraction of a surface area of the pads. Processes such as thermal compression bonding using solder pads as described are also shown.

According to one embodiment, a first electrode is formed on a first face of a first semiconductor chip, and a second electrode and a protrusion are formed on a second face of a second semiconductor chip. The first semiconductor chip and the second semiconductor chip are spaced from one another by the protrusion in such a manner that the first face and the second face face each other. The first semiconductor chip and the second semiconductor chip are subject to reflow to be electrically connected to each other, and then the protrusion is cured at a temperature lower than a reflow temperature.

According to one embodiment, a first electrode is formed on a first face of a first semiconductor chip, and a second electrode and a protrusion are formed on a second face of a second semiconductor chip. The first semiconductor chip and the second semiconductor chip are spaced from one another by the protrusion in such a manner that the first face and the second face face each other. The first semiconductor chip and the second semiconductor chip are subject to reflow to be electrically connected to each other, and then the protrusion is cured at a temperature lower than a reflow temperature.

A method for manufacturing metal powder comprising: providing a basic metal salt solution; contacting the basic metal salt solution with a reducing agent to precipitate metal powder therefrom; and recovering precipitated metal powder from the solvent.

A method for manufacturing metal powder comprising: providing a basic metal salt solution; contacting the basic metal salt solution with a reducing agent to precipitate metal powder therefrom; and recovering precipitated metal powder from the solvent.

According to various embodiments, a semiconductor device may include: at least one first contact pad on a front side of the semiconductor device; at least one second contact pad on the front side of the semiconductor device; a layer stack disposed at least partially over the at least one first contact pad, wherein the at least one second contact pad is at least partially free of the layer stack; wherein the layer stack includes at least an adhesion layer and a metallization layer; and wherein the metallization layer includes a metal alloy and wherein the adhesion layer is disposed between the metallization layer and the at least one first contact pad for adhering the metal alloy of the metallization layer to the at least one first contact pad.

According to various embodiments, a semiconductor device may include: at least one first contact pad on a front side of the semiconductor device; at least one second contact pad on the front side of the semiconductor device; a layer stack disposed at least partially over the at least one first contact pad, wherein the at least one second contact pad is at least partially free of the layer stack; wherein the layer stack includes at least an adhesion layer and a metallization layer; and wherein the metallization layer includes a metal alloy and wherein the adhesion layer is disposed between the metallization layer and the at least one first contact pad for adhering the metal alloy of the metallization layer to the at least one first contact pad.

A method of bonding a plurality of die having first and second metal layers on a die surface to a board, comprising placing a first die onto a board comprising one of a ceramic or substrate board or metal lead frame having a solderable surface and placing the first die and the board into a reflow oven. The method includes reflowing at a first reflow temperature for a first period until the first metal board layer and at least one of the first and second metal die layers of the first die form an alloy to adhere the first die to the board. The newly formed alloy has a higher melting temperature than the first reflow temperature. Accordingly, additional die may be reflowed and attached to the board without causing the bonding of the first die to the board to fail if the same reflow temperature is used.

Highly reliable chip mounting is accomplished by using a substrate having such a shape that a stress exerted on a flip-chip-connected chip can be reduced, so that the stress exerted on the chip is reduced and separation of an interlayer insulating layer having a low dielectric constant (low-k) is minimized. Specifically, in a chip mounting structure, a chip including an interlayer insulating layer having a low dielectric constant (low-k) is flip-chip connected to a substrate via bumps is shown. In the chip mounting structure, the substrate has such a shape that a mechanical stress exerted on the interlayer insulating layer at corner portions of the chip due to a thermal stress is reduced, the thermal stress occurring due to a difference in coefficient of thermal expansion between the chip and the substrate.

Semiconductor structures and methods are provided. An exemplary method includes receiving a structure comprising a metal feature, a first passivation structure over the metal feature, and a first opening extending through the first passivation structure and exposing the metal feature. The exemplary method also includes forming a conductive layer in the first opening; forming a second passivation structure over the conductive layer, performing a first etching process to form a second opening extending through the second passivation structure and exposing the conductive layer, performing a second etching process to selectively remove an upper portion of the second passivation structure to enlarge an upper portion of the second opening, and after the performing of the second etching process, forming a conductive feature in the second opening.