Forming aluminum circuit layers forming an aluminum circuit layers on one surface of a ceramic substrate and forming copper circuit layers are included. The copper circuit layers are formed by laminating copper boards for the circuit layers on the respective aluminum circuit layers, arranging the laminate between a pair of support boards having a convex curved surface at least on one surface so as to face to each other, moving the support boards in a facing direction to press the laminate in a lamination direction, and heating in this pressing state so that the copper boards for the circuit layers are bonded on the aluminum circuit layers respectively by solid phase diffusion. In the step of forming the copper circuit layers, the support boards are arranged so that either one of the convex curved surface is in contact with the adjacent copper boards for the circuit layers in the laminate.

The present invention provides a collector plate including a porous ultra-thin copper foil made by the method for manufacturing porous ultra-thin copper foil. One of surfaces of the porous ultra-thin copper foil has a plurality of pores and the thickness of the porous ultra-thin copper foil is between 1 and 5 micron.

The present invention provides an ultra-thin copper foil structure including a carrier layer, a separation layer, and an ultra-thin copper layer. The carrier layer has a predetermined surface. The separation layer is formed on the predetermined surface of the carrier layer. The ultra-thin copper layer is disposed on the carrier layer through the separation layer. The separation layer includes at least two of nickel, molybdenum, chromium, and their salts.

An electroconductive substrate, including: a base material; a foundation layer disposed on the base material; a trench formation layer disposed on the foundation layer, and an electroconductive pattern layer including metal plating. A trench including a bottom surface to which the foundation layer is exposed, is formed. The trench is filled with the electroconductive pattern layer. The foundation layer includes a mixed region which is formed from a surface of the foundation layer on the electroconductive pattern layer side towards the inside thereof, and contains metal particles which contain a metal configuring the electroconductive pattern layer, and enter the foundation layer.

An electroconductive substrate, including: a base material; a foundation layer disposed on the base material; a trench formation layer disposed on the foundation layer, and an electroconductive pattern layer including metal plating. A trench including a bottom surface to which the foundation layer is exposed, is formed. The trench is filled with the electroconductive pattern layer. The foundation layer includes a mixed region which is formed from a surface of the foundation layer on the electroconductive pattern layer side towards the inside thereof, and contains metal particles which contain a metal configuring the electroconductive pattern layer, and enter the foundation layer.

A technique for making a glass core substrate that is less prone to cracking. A core substrate of the present invention includes a glass plate and a first conductor pattern provided on a first main surface of the glass plate. The first conductor pattern includes a first nickel plating layer that is provided on the first main surface of the glass plate and has a phosphorus content of 5 mass % or less and a first copper plating layer that is provided on the first nickel plating layer.

The method for manufacturing an insulated circuit board of the present invention includes: a ceramic/aluminum-joining step of joining an aluminum material to a ceramic substrate and thereby, forming an aluminum layer; a titanium material-disposing step of disposing a titanium material on a surface of the aluminum layer or the aluminum material in a circuit pattern shape; a titanium layer-forming step of performing a heat treatment in a state where the titanium material is laminated on the surface of the aluminum layer or the aluminum material and thereby, forming the titanium layer; and an etching treatment step of etching the aluminum layer on which the titanium layer is formed, into the circuit pattern shape.

Embodiments disclosed herein include electronic packages and methods of forming such packages. In an embodiment, the electronic package comprises a substrate and a conductive feature over the substrate. In an embodiment, a metallic mask is positioned over the conductive feature. In an embodiment, the metallic mask extends beyond a first edge of the conductive feature and a second edge of the conductive feature.

A manufacturing method of a composite substrate is provided. A first conductive layer is formed on a first liquid crystal polymer layer. The first conductive layer is patterned to form a patterned first conductive layer. A second liquid crystal polymer layer including a soluble liquid crystal polymer is formed to cover the patterned first conductive layer. The second liquid crystal polymer layer which is on the patterned first conductive layer is removed.

A method for manufacturing the circuit board comprises following steps of forming a silver layer on each of two opposite surfaces of an insulating substrate, and forming a copper layer on each silver layer, thereby obtaining a middle structure; defining at least one through-hole on the middle structure, and each through-hole extending through each copper layer; forming a copper wiring layer on the copper layers to cover each through-hole and a portion region of the copper layers, the copper wiring layer comprising a copper conductive structure passing through each through-hole, the copper conductive structure connecting the copper layers; removing the copper layers not covered by the copper wiring layer; and etching the silver layers to form a silver wiring layer corresponding to the copper wiring layer, wherein a first etching liquid, which does not etch the copper wiring layer, is used for etching the silver layers.