A semiconductor device includes a substrate. A conductive layer is disposed on the substrate and extends in a first direction. An insulating layer is disposed on the conductive layer and exposes at least a portion of the conductive layer through a via hole. The via hole includes a first face extending in a first slope relative to a top face of the conductive layer. A second face extends in a second slope relative to the top face of the conductive layer that is less than the first slope. A redistribution conductive layer includes a first pad area disposed in the via hole. A line area at least partially extends along the first face and the second face. The first face directly contacts the conductive layer. The second face is positioned at a higher level than the first face in a second direction perpendicular to a top face of the substrate.

An electrodeposition composition comprising: (a) a source of copper ions; (b) an acid; (c) a suppressor; and (d) a leveler, wherein the leveler comprises a quaternized dipyridyl compound prepared by reacting a dipyridyl compound with a difunctional alkylating agent or a quaternized poly(epihalohydrin). The electrodeposition composition can be used in a process for forming a copper feature over a semiconductor substrate in wafer level packaging to electrodeposit a copper bump or pillar on an underbump structure of a semiconductor assembly.

An electrodeposition composition comprising: (a) a source of copper ions; (b) an acid; (c) a suppressor; and (d) a leveler, wherein the leveler comprises a quaternized dipyridyl compound prepared by reacting a dipyridyl compound with a difunctional alkylating agent or a quaternized poly(epihalohydrin). The electrodeposition composition can be used in a process for forming a copper feature over a semiconductor substrate in wafer level packaging to electrodeposit a copper bump or pillar on an underbump structure of a semiconductor assembly.

In some examples, a quad flat no lead (QFN) semiconductor package comprises a flip chip semiconductor die having a surface and circuitry formed in the surface; and a conductive pillar coupled to the semiconductor die surface. The conductive pillar has a distal end relative to the semiconductor die, the distal end having a cavity including a cavity floor and one or more cavity walls circumscribing the cavity floor. The one or more cavity walls are configured to contain solder.

A flexible circuit board according to an embodiment of the present invention comprises: a substrate; a first wiring pattern layer disposed on a first surface of the substrate; a second wiring pattern layer disposed on a second surface opposite the first surface of the substrate; a first dummy pattern part disposed on the second surface of the substrate on which the second wiring pattern layer is not disposed; a first protection layer disposed on the first wiring pattern layer; and a second protection layer disposed on the second wiring pattern layer and the first dummy pattern part, wherein at least a part of the first dummy pattern part overlaps with the first wiring pattern layer in a vertical direction.

A flexible circuit board according to an embodiment of the present invention comprises: a substrate; a first wiring pattern layer disposed on a first surface of the substrate; a second wiring pattern layer disposed on a second surface opposite the first surface of the substrate; a first dummy pattern part disposed on the second surface of the substrate on which the second wiring pattern layer is not disposed; a first protection layer disposed on the first wiring pattern layer; and a second protection layer disposed on the second wiring pattern layer and the first dummy pattern part, wherein at least a part of the first dummy pattern part overlaps with the first wiring pattern layer in a vertical direction.

The disclosed technique may be used to electrically and physically connect semiconductor wafers. The wafer may utilize a thick dielectric. Indium bumps may be deposited and patterned in a dielectric film with a small diameter, tall height and substantially uniform in size and shape. The indium can be melted to create small grain size and uniform height bumps. The dielectric film may feature trenches around the indium bumps to prevent shorting of pixels when pressed together.

The disclosed technique may be used to electrically and physically connect semiconductor wafers. The wafer may utilize a thick dielectric. Indium bumps may be deposited and patterned in a dielectric film with a small diameter, tall height and substantially uniform in size and shape. The indium can be melted to create small grain size and uniform height bumps. The dielectric film may feature trenches around the indium bumps to prevent shorting of pixels when pressed together.

Techniques regarding forming flip chip interconnects are provided. For example, one or more embodiments described herein can comprise a three-dimensionally printed flip chip interconnect that includes an electrically conductive ink material that is compatible with a three-dimensional printing technology. The three-dimensionally printed flip chip interconnect can be located on a metal surface of a semiconductor chip.

Techniques regarding forming flip chip interconnects are provided. For example, one or more embodiments described herein can comprise a three-dimensionally printed flip chip interconnect that includes an electrically conductive ink material that is compatible with a three-dimensional printing technology. The three-dimensionally printed flip chip interconnect can be located on a metal surface of a semiconductor chip.