Examples are disclosed related to forming solder joints between printed circuits by using radiant heat. One example provides a method of manufacturing an electronic device, the method comprising aligning a contact of a first printed circuit with a via of a second printed circuit. The method further comprises applying radiant heat via an infrared light source to a second surface of the second printed circuit, the radiant heat incident on the via to cause the via to conduct heat to solder located at an interface of the contact and the via, and after heating the solder to reflow, cooling the solder, thereby forming a solder joint between the contact of the first printed circuit and the via of the second printed circuit.

A method for producing a glass substrate according to the present invention includes the steps of: (I) forming a through hole (11) in a glass sheet (10); (II) forming a resin layer (20) on a first principal surface of the glass sheet (10) using a resin composition sensitive to light having a predetermined wavelength .sub.1; (III) photoexposing an area of the resin layer (20) that covers the through hole (11) by irradiating the area with light U having the wavelength .sub.1 and applied from the direction of a second principal surface of the glass sheet (10); and (IV) forming a through-resin hole (21) by removing the area photoexposed in the step (III). The glass sheet (10) protects the resin layer (20) from the light U so as to prevent the resin layer (20) from being photoexposed by beams of the light U that are incident on the second principal surface of the glass sheet (10) in the step (III).

A vertical circuit board printer includes a multi-layer conveyor, a printer assembly, and a control system. The multi-layer conveyor includes a number of front conveyors and one rear conveyor. Each upper front conveyor is coupled to a lower front conveyor by a circuit board-lowering mechanism to transport a number of circuit boards in sequence from the number of front conveyors to the rear conveyor. The printer assembly includes a number of printers arranged in sequence above the number of front conveyors. The control system controls operation of the multi-layer conveyor and controls operation of the printing assembly through a software system.

A method for producing a glass substrate according to the present invention includes the steps of: (I) forming a through hole (11) in a glass sheet (10); (II) forming a resin layer (20) on a first principal surface of the glass sheet (10) using a resin composition sensitive to light having a predetermined wavelength .sub.1; (III) photoexposing an area of the resin layer (20) that covers the through hole (11) by irradiating the area with light U having the wavelength .sub.1 and applied from the direction of a second principal surface of the glass sheet (10); and (IV) forming a through-resin hole (21) by removing the area photoexposed in the step (III). The glass sheet (10) protects the resin layer (20) from the light U so as to prevent the resin layer (20) from being photoexposed by beams of the light U that are incident on the second principal surface of the glass sheet (10) in the step (III).

A bonding method of a flexible display module is provided. The flexible display module includes a flexible display panel having a first bonding area and an integrated driving circuit having a second bonding area. The bonding method includes: attaching, through a colloid, a transfer plate to a surface of the flexible display panel; solidifying the colloid facing the first bonding area to form a fixed portion; flattening the transfer plate to flatten the first bonding area through the fixed portion; aligning the second bonding area with the first bonding area pre-laminating the first bonding area and the second bonding area at a first temperature; breaking the fixed portion, and separating the flexible display panel and the transfer plate; flattening the flexible display panel; laminating the first bonding area and the second bonding area at a second temperature to form the flexible display module.

An electronic device capable of supplying a large current to a circuit pattern containing conductive nanoparticles includes a substrate, a region provided on the substrate, configured to mount an electronic component therein, a first circuit pattern placed within the region and electrically connected to the electronic component, a second circuit pattern connected to the first circuit pattern and configured to supply current to the first circuit pattern from outside of the region. At least a part of the first circuit pattern includes a layer obtained by sintering conductive nanosized particles with a diameter of less than 1 m. The second circuit pattern is thicker than the first circuit pattern.

According to some aspects of the present disclosure, circuit board assemblies are disclosed. Example circuit board assemblies include a printed circuit board having a first surface and a second surface, and defining an opening having at least one side extending from the first surface to the second surface. The assembly also includes a bus bar having a first surface, a second surface, and at least one side. The bus bar is secured in the opening of the printed circuit board via a press-fit, such that a slot is defined between the at least one side of the bus bar and the at least one side of the opening defined by the printed circuit board. The assembly further includes an electrical lead positioned in the slot, and solder disposed between the electrical lead and the bus bar to electrically couple the electrical lead and the bus bar.

According to some aspects of the present disclosure, circuit board assemblies are disclosed. Example circuit board assemblies include a printed circuit board having a first surface and a second surface, and defining an opening having at least one side extending from the first surface to the second surface. The assembly also includes a bus bar having a first surface, a second surface, and at least one side. The bus bar is secured in the opening of the printed circuit board via a press-fit, such that a slot is defined between the at least one side of the bus bar and the at least one side of the opening defined by the printed circuit board. The assembly further includes an electrical lead positioned in the slot, and solder disposed between the electrical lead and the bus bar to electrically couple the electrical lead and the bus bar.

The present invention discloses a method for preparing a novel material layer structure of a circuit board, comprising the steps of: (1) combining a film with a copper layer to form an FCCL single-sided board; (2) applying a semi-cured functional material layer on a back side of the film of the FCCL single-sided board, wherein the semi-cured functional material layer is an MPI film, an LCP film, a TFP film, a PTFE film, a copper ion migration resistant film, an LDK high-frequency functional adhesive, a copper ion migration resistant adhesive, or a mixture of the LDK high-frequency functional adhesive and the copper ion migration resistant adhesive to form a novel material layer structure for a circuit board. An article prepared by performing the above methods is also disclosed. The prepared novel material layer structure of the circuit board has high-frequency characteristics and/or copper ion migration resistance, and can be used as an integral structure. In the circuit board manufacturing process, it can be manufactured as the circuit board manufacturing material to be different circuit board structures, which brings great convenience for subsequent circuit board manufacturing and simplifies the manufacturing process.

An electronic device can include a plurality of pad electrodes provided at at least one side of a substrate, at least one circuit film configured to have a plurality of connection electrodes provided at an insulating film to correspond to the plurality of pad electrodes, a plurality of solders to conductively connect the plurality of connection electrodes to the plurality of pad electrodes exposed from the circuit film one-to-one, and an insulating adhesive to fill spaces between the plurality of pad electrodes and the plurality of connection electrodes. Also, each of the plurality of solders has an edge horizontally protruding from the insulating film.