In a plating method, a laminate made of stainless steel, and copper or a copper alloy is prepared. Plating underlayers made of nickel are formed on a first plated portion provided at the stainless steel and a second plated portion provided at the copper or the copper alloy at the same time with use of a hydrochloric acid electrolytic solution.

In a plating method, a laminate made of stainless steel, and copper or a copper alloy is prepared. Plating underlayers made of nickel are formed on a first plated portion provided at the stainless steel and a second plated portion provided at the copper or the copper alloy at the same time with use of a hydrochloric acid electrolytic solution.

The invention pertains to a method for the bonding of a component embedded into a printed circuit board exhibiting the following steps: Provision of a core exhibiting at least one insulating layer and at least one conductor layer applied to the insulating layer, Embedding of at least one component into a recess of the insulating layer, wherein the contacts of the component are essentially situated in the plane of an outer surface of the core exhibiting the at least one conductor layer, Application of a photoimageable resist onto the one outer surface of the core on which the component is arranged, while filling the spaces between the contacts of the component, Clearing of end faces of the contacts and of the areas of the conductor layer covered by the photoimageable resist by exposing and developing the photoimageable resist, by application of a semi-additive process, deposition of a layer of conductor material onto the cleared end faces of the contacts and the cleared areas of the conductor layer and formation of a conductor pattern on at least the one outer surface of the core on which the component is arranged, as well as the interconnecting paths between the contacts and the conductor pattern, and Removal of the areas of the conductor layer not belonging to the conductor pattern.

The invention relates to a washing solution for a tin plating film after electroless tin plating and before water washing. The invention also relates to a method for forming a tin plating film, the method includes a step of washing step using the washing solution. The washing solution according to the present invention is an acidic aqueous solution containing an acid, a complexing agent, a stabilizer and a chloride ion. The washing solution has a chloride ion concentration of 2 wt % or more, and a tin concentration of 0.5 wt % or less. The washing solution according to the present invention has good washing property for a tin plating film surface, and allows a tin plating film to easily maintain its properties. In addition the washing solution causes little influence on a tin plating film surface even when continuously used and is excellent in temporal stability.

The invention relates to a washing solution for a tin plating film after electroless tin plating and before water washing. The invention also relates to a method for forming a tin plating film, the method includes a step of washing step using the washing solution. The washing solution according to the present invention is an acidic aqueous solution containing an acid, a complexing agent, a stabilizer and a chloride ion. The washing solution has a chloride ion concentration of 2 wt % or more, and a tin concentration of 0.5 wt % or less. The washing solution according to the present invention has good washing property for a tin plating film surface, and allows a tin plating film to easily maintain its properties. In addition the washing solution causes little influence on a tin plating film surface even when continuously used and is excellent in temporal stability.

A resin film containing a fluororesin as a main component has, on at least one surface thereof, a pre-treated surface having a content ratio of oxygen atoms or nitrogen atoms of 0.2 atomic percent or more. A coverlay includes the resin film and an adhesive layer laminated on the pre-treated surface. A substrate for a printed wiring board includes the resin film and a conductive layer laminated on the pre-treated surface. A printed wiring board includes an insulating base layer, a conductive pattern laminated on at least one surface of the base layer, and the coverlay for a printed wiring board, the coverlay being laminated on the conductive pattern.

A resin film containing a fluororesin as a main component has, on at least one surface thereof, a pre-treated surface having a content ratio of oxygen atoms or nitrogen atoms of 0.2 atomic percent or more. A coverlay includes the resin film and an adhesive layer laminated on the pre-treated surface. A substrate for a printed wiring board includes the resin film and a conductive layer laminated on the pre-treated surface. A printed wiring board includes an insulating base layer, a conductive pattern laminated on at least one surface of the base layer, and the coverlay for a printed wiring board, the coverlay being laminated on the conductive pattern.

A method of etching an electrically conductive layer structure during manufacturing a component carrier is provided. The method includes carrying out a first etching of at least one exposed region of an electrically conductive layer structure by a first etching composition having a photo-hardenable compound to thereby form a recess in the electrically conductive layer structure, hardening the photo-hardenable compound by irradiation with photons selectively on an upper side wall portion of the recess to thereby cover the upper side wall portion with a photo-hardened compound, carrying out a second etching by a second etching composition selectively on a side wall portion and/or bottom portion of the recess being not covered with the photo-hardened compound, and subsequently removing the photo-hardened compound from the side wall portion. In addition, a component carrier is provided.

A method of etching an electrically conductive layer structure during manufacturing a component carrier is provided. The method includes carrying out a first etching of at least one exposed region of an electrically conductive layer structure by a first etching composition having a photo-hardenable compound to thereby form a recess in the electrically conductive layer structure, hardening the photo-hardenable compound by irradiation with photons selectively on an upper side wall portion of the recess to thereby cover the upper side wall portion with a photo-hardened compound, carrying out a second etching by a second etching composition selectively on a side wall portion and/or bottom portion of the recess being not covered with the photo-hardened compound, and subsequently removing the photo-hardened compound from the side wall portion. In addition, a component carrier is provided.

An opto-electric hybrid board includes: an electric circuit board including an insulation layer haying front arid back surfaces, arid electrical interconnect lines formed on the front surface of the insulation layer; and an optical waveguide having a substantially rectangular shape as seen in plan view and provided on the back surface of the insulation layer of the electric circuit board, with a metal layer therebetween. The optical waveguide has at least one end portion disposed in overlapping relation with the metal layer. The at least one end portion of the optical waveguide has corner portions. Each of the corner portions is radiused to have an arcuate shape or has a polygonal shape produced by arranging a plurality of obtuse-angled portions in a substantially arcuate configuration.