A method for forming a circuit board having a dielectric core, a foil top surface, and a thin foil bottom surface with a removable foil backing of sufficient thickness to absorb heat from a laser drilling operation to prevent the penetration of the thin foil bottom surface during laser drilling utilizes a sequence of steps including a laser drilling step, removing the foil backing step, electroless plating step, patterned resist step, electroplating step, resist strip step, tin plate step, and copper etch step, which provide dot vias of fine linewidth and resolution.

A method for manufacturing a printed wiring board includes forming an electroless plating layer on a solder resist layer such that the electroless plating layer has a film thickness in the range of 0.05 μm to 0.70 μm, forming plating resist such that the plating resist has openings exposing portions of the electroless plating layer, applying electrolytic plating such that metal posts are formed in the openings of the plating resist, removing the plating resist, and etching the electroless plating layer exposed from the metal posts. The solder resist layer is formed such that the solder resist layer has openings exposing portions of the outermost conductor layer, the electroless plating layer is formed on the portions of the outermost conductor layer, and the plating resist is formed such that the openings of the plating resist expose the portions of the electroless plating layer formed in the openings of the solder resist layer.

A method for manufacturing a printed wiring board includes forming an electroless plating layer on a solder resist layer such that the electroless plating layer has a film thickness in the range of 0.05 μm to 0.70 μm, forming plating resist such that the plating resist has openings exposing portions of the electroless plating layer, applying electrolytic plating such that metal posts are formed in the openings of the plating resist, removing the plating resist, and etching the electroless plating layer exposed from the metal posts. The solder resist layer is formed such that the solder resist layer has openings exposing portions of the outermost conductor layer, the electroless plating layer is formed on the portions of the outermost conductor layer, and the plating resist is formed such that the openings of the plating resist expose the portions of the electroless plating layer formed in the openings of the solder resist layer.

The present application provides a method for improving a pit defect formed after a copper electroplating process, comprising: forming a dielectric layer on a wafer; etching the dielectric layer to form a trench; forming a seed barrier layer on the surface of the trench; pre-cleaning the wafer to increase the wetness of the trench on the wafer; filling the trench with copper by means of electroplating; polishing the upper surface of the trench to planarize the upper surface of the trench. The wetness of the wafer surface can be increased by pre-cleaning a via. An excessively dry wafer surface leads to a poor wetness effect when the wafer enters water, a bubble is difficult to be discharged, a void is easy to be generated in electroplating. By the pre-cleaning step, the problem of a poor wetness effect occurring when the wafer enters water can be effectively improved.

A terminal material for a connector provided with a base material in which at least a surface layer is made of copper or copper alloy, a nickel-plating layer made of nickel or nickel alloy and formed on a surface of the base material, a silver-nickel alloy plating layer made of silver-nickel alloy and formed on at least a part of the nickel-plating layer, and a silver-plating layer made of silver and formed on the silver-nickel alloy plating layer; the silver-nickel alloy plating layer has a film thickness 0.05 .Math.m or more and less than 0.50 .Math.m and a nickel content 0.03 at% or more and 1.00 at% or less.

A manufacturing method of copper foil and circuit board assembly for high frequency transmission are provided. Firstly, a raw copper foil having a predetermined surface is produced by an electrolyzing process. Subsequently, a roughened layer including a plurality of copper particles is formed on the predetermined surface by an arsenic-free electrolytic roughening treatment and an arsenic-free electrolytic surface protection treatment. Thereafter, a surface treatment layer is formed on the roughened layer, and the roughened layer is made of a material which includes at least one kind of non-copper metal elements and the concentration of the non-copper metal elements is smaller than 400 ppm. By controlling the concentration of the non-copper elements, the resistance of the copper foil can be reduced.

A manufacturing method of copper foil and circuit board assembly for high frequency transmission are provided. Firstly, a raw copper foil having a predetermined surface is produced by an electrolyzing process. Subsequently, a roughened layer including a plurality of copper particles is formed on the predetermined surface by an arsenic-free electrolytic roughening treatment and an arsenic-free electrolytic surface protection treatment. Thereafter, a surface treatment layer is formed on the roughened layer, and the roughened layer is made of a material which includes at least one kind of non-copper metal elements and the concentration of the non-copper metal elements is smaller than 400 ppm. By controlling the concentration of the non-copper elements, the resistance of the copper foil can be reduced.

A copper alloy plate containing in a center part of a plate thickness direction more than 2.0% (% by mass) and 32.5% or less of Zn; 0.1% or more and 0.9% or less of Sn; 0.05% or more and less than 1.0% of Ni; 0.001% or more and less than 0.1% of Fe, and 0.005% or more and 0.1% or less of P; and the balance Cu, including a surface layer part in which a surface Zn concentration in a surface is 60% or less of a center Zn concentration in the center part, having a depth from the surface to where Zn concentration is 90% of the center Zn concentration; and in the surface layer, the Zn concentration increases from the surface toward the center part in the plate thickness direction at a concentration gradient of 10% by mass/μm or more and 1000% by mass/μm or less.

The present invention is directed to provide novel composite copper components. For example, provided is a composite copper component including a copper oxide-containing layer formed on at least a portion of the surface of a copper component, in which when the surface of the composite copper component is bonded to a resin substrate by thermocompression, and the copper component is peeled off from the resin substrate after the thermocompression bonding, metal contained in the copper oxide-containing layer is transferred to the resin substrate.

There is provided a bonding wire for semiconductor devices that exhibits a favorable bondability even when being applied to wedge bonding at the room temperature, and also achieves an excellent bond reliability. The bonding wire includes a core material of Cu or Cu alloy (hereinafter referred to as a “Cu core material”), and a coating containing a noble metal formed on a surface of the Cu core material. A concentration of Cu at a surface of the wire is 30 to 80 at%.