Die stacks and methods of making die stacks with very thin dies are disclosed. The die surfaces remain flat within a 5 micron tolerance despite the thinness of the die and the process steps of making the die stack. A residual flux height is kept below 50% of the spacing distance between adjacent surfaces or structures, e.g. in the inter-die spacing.

Die stacks and methods of making die stacks with very thin dies are disclosed. The die surfaces remain flat within a 5 micron tolerance despite the thinness of the die and the process steps of making the die stack. A residual flux height is kept below 50% of the spacing distance between adjacent surfaces or structures, e.g. in the inter-die spacing.

An integrated circuit assembly including a substrate having a surface including at least one area including contact points operable for connection with an integrated circuit die; and at least one ring surrounding the at least one area, the at least one ring including an electrically conductive material. A method of forming an integrated circuit assembly including forming a plurality of electrically conductive rings around a periphery of a die area of a substrate selected for attachment of at least one integrated circuit die, wherein the plurality of rings are formed one inside the other; and forming a plurality of contact points in the die area.

An integrated circuit assembly including a substrate having a surface including at least one area including contact points operable for connection with an integrated circuit die; and at least one ring surrounding the at least one area, the at least one ring including an electrically conductive material. A method of forming an integrated circuit assembly including forming a plurality of electrically conductive rings around a periphery of a die area of a substrate selected for attachment of at least one integrated circuit die, wherein the plurality of rings are formed one inside the other; and forming a plurality of contact points in the die area.

The present disclosure provides devices and methods in which a semiconductor chip has a reduced size and thickness. The device is manufactured by utilizing a sacrificial or dummy silicon wafer. A recess is formed in the dummy silicon wafer where the semiconductor chip is mounted in the recess. The space between the dummy silicon wafer and the chip is filled with underfill material. The dummy silicon wafer and the backside of the chip are etched using any suitable etching process until the dummy silicon wafer is removed, and the thickness of the chip is reduced. With this process, the overall thickness of the semiconductor chip can be thinned down to less than 50 μm in some embodiments. The ultra-thin semiconductor chip can be incorporated in manufacturing flexible/rollable display panels, foldable mobile devices, wearable displays, or any other electrical or electronic devices.

The present disclosure provides devices and methods in which a semiconductor chip has a reduced size and thickness. The device is manufactured by utilizing a sacrificial or dummy silicon wafer. A recess is formed in the dummy silicon wafer where the semiconductor chip is mounted in the recess. The space between the dummy silicon wafer and the chip is filled with underfill material. The dummy silicon wafer and the backside of the chip are etched using any suitable etching process until the dummy silicon wafer is removed, and the thickness of the chip is reduced. With this process, the overall thickness of the semiconductor chip can be thinned down to less than 50 μm in some embodiments. The ultra-thin semiconductor chip can be incorporated in manufacturing flexible/rollable display panels, foldable mobile devices, wearable displays, or any other electrical or electronic devices.

An electronic-part-reinforcing thermosetting resin composition has: a viscosity of 5 Pa.Math.s or less at 140° C.; a temperature of 150° C. to 170° C. as a temperature corresponding to a maximum peak of an exothermic curve representing a curing reaction; and a difference of 20° C. or less between the temperature corresponding to the maximum peak and a temperature corresponding to one half of the height of the maximum peak in a temperature rising range of the exothermic curve.

An electronic-part-reinforcing thermosetting resin composition has: a viscosity of 5 Pa.Math.s or less at 140° C.; a temperature of 150° C. to 170° C. as a temperature corresponding to a maximum peak of an exothermic curve representing a curing reaction; and a difference of 20° C. or less between the temperature corresponding to the maximum peak and a temperature corresponding to one half of the height of the maximum peak in a temperature rising range of the exothermic curve.

An optical module includes an optical semiconductor chip including a first electrode pad, a second electrode pad, and a third electrode pad arranged between the first electrode pad and the second electrode pad, a wiring substrate on which the optical semiconductor chip is flip-chip mounted, including a fourth electrode pad, a fifth electrode pad, and a sixth electrode pad arranged between the fourth electrode pad and the fifth electrode pad, a first conductive material connecting the first electrode pad with the fourth electrode pad, a second conductive material connecting the second electrode pad with the fifth electrode pad, a third conductive material arranged between the first conductive material and the second conductive material, connecting the third electrode pad with the sixth electrode pad, and a resin provided in an area on the second conductive material side of the third conductive material between the optical semiconductor chip and the wiring substrate.

An optical module includes an optical semiconductor chip including a first electrode pad, a second electrode pad, and a third electrode pad arranged between the first electrode pad and the second electrode pad, a wiring substrate on which the optical semiconductor chip is flip-chip mounted, including a fourth electrode pad, a fifth electrode pad, and a sixth electrode pad arranged between the fourth electrode pad and the fifth electrode pad, a first conductive material connecting the first electrode pad with the fourth electrode pad, a second conductive material connecting the second electrode pad with the fifth electrode pad, a third conductive material arranged between the first conductive material and the second conductive material, connecting the third electrode pad with the sixth electrode pad, and a resin provided in an area on the second conductive material side of the third conductive material between the optical semiconductor chip and the wiring substrate.