Abstract: In a semiconductor device (1), a package board (2) is provided in which a plurality of wiring layers are layered, a plurality of mounting pads (5) arranged in a matrix are provided to the uppermost wiring layer of the package board (2), and solder bumps (7) are connected to the mounting pads (5). A semiconductor chip (9) is mounted on the package board (2) via the solder bumps (7). The uppermost wiring layer of the package board (2) is formed from a resin material in which the Young's modulus is 1 GPa or lower when the temperature is 10 to 30° C., and the elongation at break is 50% or higher.

Abstract: In a semiconductor device, the topmost wiring layer of the package board is formed from an insulation material in which the elongation at break is 20% or higher and Young's modulus is 1 GPa or less when the temperature is 10 to 30° C. This insulation material contains a reactive elastomer that reacts with epoxy resin or an epoxy resin curing agent; an epoxy resin; an epoxy resin curing agent; and a crosslinked styrene-butadiene rubber having a double bond and a hydroxyl group, a carboxylic group, or another polar group. It is therefore possible to provide a semiconductor device that has a wiring board in which the connection reliability in relation to temperature cycles is high and the adhesiveness between the insulation layer and the electroless copper plating layer is also high.

Abstract: In a semiconductor device (1), a package board (2) is provided in which a plurality of wiring layers are layered, a plurality of mounting pads (5) arranged in a matrix are provided to the uppermost wiring layer of the package board (2), and solder bumps (7) are connected to the mounting pads (5). A semiconductor chip (9) is mounted on the package board (2) via the solder bumps (7). The uppermost wiring layer of the package board (2) is formed from a resin material in which the Young's modulus is 1 GPa or lower when the temperature is 10 to 30° C., and the elongation at break is 50% or higher.

Abstract: In a semiconductor device, the topmost wiring layer of the package board is formed from an insulation material in which the elongation at break is 20% or higher and Young's modulus is 1 GPa or less when the temperature is 10 to 30° C. This insulation material contains a reactive elastomer that reacts with epoxy resin or an epoxy resin curing agent; an epoxy resin; an epoxy resin curing agent; and a crosslinked styrene-butadiene rubber having a double bond and a hydroxyl group, a carboxylic group, or another polar group. It is therefore possible to provide a semiconductor device that has a wiring board in which the connection reliability in relation to temperature cycles is high and the adhesiveness between the insulation layer and the electroless copper plating layer is also high.