Abstract:
In a method for manufacturing a printed circuit board, a substrate, including a number of plated through holes (PTHs) is provided. Each of the PTHs has an electrically conductive layer plated on its inner wall and includes an electrically connecting portion and a stub. A protective layer is formed on a surface of the substrate adjacent to the stub. An etching device, including an upper plate and a number of spray tubes corresponding to the PTHs, is provided. Each of the spray tubes includes a protruding portion beyond the upper plate. The substrate is arranged in such a manner that the protective layer is in contact with the upper plate and the protruding portions are received in the stubs. After that, the protruding portions spray an etchant to etch and remove the electrically conductive layer of the stubs, and the protective layer is removed.
Abstract:
An exemplary ink for forming electrical traces includes an aqueous carrier medium, a palladium salt and a reducing agent. The palladium salt is capable of being dissolved in the aqueous carrier medium. The reducing agent is configured for reducing the palladium ions into palladium particles under an irradiation ray.
Abstract:
An electromagnetic shielding composite includes a polymer and a carbon nanotube film structure. The carbon nanotube structure includes a number of carbon nanotubes disposed in the polymer. The number of carbon nanotubes are parallel with each other.
Abstract:
A method for forming electrical traces on a substrate includes the steps of: providing a substrate; printing an ink pattern using an ink on the substrate, the ink including a aqueous medium containing silver ions and a heat sensitive reducing agent; heating the ink pattern to reduce silver ions into silver particles thereby forming an semi-finished traces; and forming a metal overcoat on the semi-finished traces by electroless plating thereby obtaining patterned electrical traces.
Abstract:
A method for manufacturing printed circuit board includes steps below. A first electrically conductive layer including a first surface and a second surface at an opposite side thereof to the first surface is provided. A number of first traces directly formed on the second surface. A first insulating layer is formed on the second surface of the first electrically conductive layer and the surface of the first traces. The electrically conductive layer is etched to form a number of second traces, the second traces superpose the first traces, the first traces and the second traces constitute a circuit pattern.
Abstract:
A method of forming electrical traces includes the steps of: providing a substrate; printing an ink pattern using a silver containing ink on the substrate, the ink comprising an aqueous carrier medium having dissolved therein a water-soluble light sensitive silver salt; irradiating the ink pattern to reduce silver salt therein to silver particles thereby forming an underlayer; and electroless plating a metal overcoat layer on the underlayer thereby obtaining electrical traces.
Abstract:
A printed circuit board includes a substrate having a surface, a circuit layer having a plurality of electrical traces formed on the surface, and an electrically conductive metal layer formed on the circuit layer. The circuit layer is comprised of a composite of carbon nano-tubes and metallic nano-particles.
Abstract:
An electroplating method includes steps of: providing a substrate having a first portion and a second portion connected to the first portion; forming a metallic layer on a surface of the second portion; immersing the first portion of the substrate in an electrolyte solution, applying a current to the metallic layer to electroplate the first portion of the substrate with a metal layer; and moving the substrate in a direction away from the electrolyte solution during electroplating the first portion of the substrate. The method can improve a uniformity of the obtained plating layer.
Abstract:
A printed circuit board includes a composite layer, a first electrically conductive pattern, and a second electrically conductive pattern. The composite layer includes a polymer matrix and an electrically conductive pin embedded therein. The polymer matrix has a first surface and an opposite second surface. The pin includes a catalyst block and a carbon nanotube bundle grown on the catalyst block. The catalyst block is exposed at the first surface, and the carbon nanotube bundle is exposed at the second surface. The first pattern is formed on the first surface, and includes a first electrical contact, which is electrically coupled to the catalyst block. The second pattern is formed on the second surface, and includes a second electrical contact, which is electrically coupled to the carbon nanotube bundle.
Abstract:
An exemplary method for forming electrical traces on a substrate includes flowing steps. Firstly, a circuit pattern is formed on the substrate by printing a silver ions-containing ink. The ink comprises an aqueous carrier medium, and a silver halide emulsion soluble in the aqueous carrier medium. Secondly, an irradiation ray irradiates the circuit pattern to reduce the silver ions into silver to form a silver particle circuit pattern comprised of silver particles. Thirdly, a metal overcoat layer is electroless-plated on the silver particle circuit pattern thereby obtaining electrical traces.