A method of fabricating an interposer includes: providing a carrier substrate; forming a unit redistribution layer on the carrier substrate, the unit redistribution layer including a conductive via plug and a conductive redistribution line; and removing the carrier substrate from the unit redistribution layer. The formation of the unit redistribution layer includes: forming a first photosensitive pattern layer including a first via hole pattern; forming a second photosensitive pattern layer including a second via hole pattern and a redistribution pattern on the first photosensitive pattern layer; at least partially filling insides of the first via hole pattern, the second via hole pattern, and the redistribution pattern with a conductive material; and performing planarization to make a top surface of the unit redistribution layer flat. According to the method, no undercut occurs under a conductive structure and there are no bubbles between adjacent conductive structures, thus device reliability is enhanced and pattern accuracy is realized.

The present invention comprises a step of forming bump pads on the surface of the substrate, covering the whole surface with a second insulating layer, forming a copper barrier on the surface of a second insulating layer, forming a third insulating layer, and forming a copper layer for an electrical circuit. A mask is formed on the copper layer of the external circuit in such a way that only the region for the cavity is exposed. The cavity is formed by laser-drilling only the surface-exposed area of the third insulating layer. The copper layer at the bottom protects the second insulating layer and bump pads underneath from laser damages. The copper barrier is removed by chemical etch once the laser drill is over. The second insulating layer will be removed via sand blast process, exposing the bump pads which were fabricated in the earlier steps.

A wiring board includes first insulating layers; first wiring layers; first via wirings; second insulating layers; second wiring layers; second via wirings; and a solder resist layer, wherein the first insulating layers are composed of non-photosensitive resin, wherein the second insulating layers, and the solder resist layer are composed of photosensitive resin, respectively, wherein the first surface of the uppermost first insulating layer and the first end surface of the first via wiring embedded in the uppermost first insulating layer are polished surfaces, wherein the first end surface of the first via wiring embedded in the uppermost first insulating layer is flush with the first surface of the uppermost first insulating layer, and wherein the wiring density of the second wiring layers is higher than the wiring density of the first wiring layers.

An electronic device module includes a substrate, a first component disposed on a first surface of the substrate, a sealing portion disposed on the first surface of the substrate, a second component disposed on the first surface of the substrate and embedded in the sealing portion, and a shielding wall at least partially disposed between the first component and the second component and including a portion having a height, with respect to the first surface of the substrate, that is lower than a height of the sealing portion.

A method for repairing a fine line is provided. Nano metal particles are filled in a defect of a circuit board. The nano metal particles in the defect are irradiated by a laser, or heated, such that the nano metal particles in the defect are metallurgically bonded to an original line of the circuit board. A surface of the circuit board is cleaned to remove residual nano metal particles on parts of the circuit board where metallurgical bonding is not performed, thereby completing line repairing of the circuit board.

An electronic component module includes a substrate including a first main surface and a second main surface, and using a side near the second main surface as a mounting side, an external terminal by a solder ball made of first solder, on the second main surface, and a first electronic component mounted by using second solder, on the first main surface, and a melting point of the first solder is higher than a melting point of the second solder.

An electronic device module includes a substrate, a first component disposed on a first surface of the substrate, a sealing portion disposed on the first surface of the substrate, a second component disposed on the first surface of the substrate and embedded in the sealing portion, and a shielding wall at least partially disposed between the first component and the second component and including a portion having a height, with respect to the first surface of the substrate, that is lower than a height of the sealing portion.

The present application provides a method for improving colour difference of an LED display screen, comprising: drilling and polishing circuit surfaces of a plurality of LED substrates; performing screen printing on the circuit surfaces of the plurality of LED substrates, and performing oil skimming on a mesh screen during the screen printing every other preset printing cycle in such a way that an ink on the mesh screen has a viscosity within a predetermined viscosity range; performing an exposure setting process on the plurality of LED substrates that have been screen printed to obtain a plurality of LED printed circuit boards; and finally assembling the plurality of LED printed circuit boards to form an LED display screen.

A connection structure includes a first substrate having first and second principal surfaces opposed to each other and includes a first thermoplastic resin; a first substrate electrode on the first principal surface; a second substrate which has a third principal surface and a fourth principal surface opposed to the third principal surface and facing the first principal surface and includes a second thermoplastic resin; a second substrate electrode on the fourth principal surface; a conductive bonding material which bonds the first and second substrate electrodes together; and an insulating adhesive which adheres the first principal surface other than a portion where the first substrate electrode is and the fourth principal surface other than a portion where the second substrate electrode is together. A bonding temperature of the bonding material is lower than a respective melting point or a respective glass transition temperature of the first and second thermoplastic resins.

Even if a print board includes through holes that are hardly filled with material previously, the through holes can be filled with filling material appropriately. The sealing film is attached to a lower surface of the print board and the filling material is supplied from the upper surface side of the print board under a vacuum atmosphere with screen printing to fill the through holes with the filling material. Then, the film is separated from the print board and the print board is disposed on the jig plate including recesses such that the through holes correspond to the recess. Thereafter, an auxiliary filling process in which the filling material is supplied again such that the filling material protrudes from the lower surface side of the through hole is performed.