An etchant composition for etching a triple layer metal wiring structure of molybdenum/copper/molybdenum or molybdenum alloy/copper/molybdenum alloy, and a use thereof are disclosed. The etchant composition includes hydrogen peroxide, glycol, an etching inhibitor, a chelating agent, an etching additive, a pH adjuster, and water, The etchant can not only slow down the decomposition of hydrogen peroxide, but also extend the lifespan of the etchant, thereby greatly reducing the costs of the etchant in the manufacturing process, and improving the safety factor of the etchant.

A method for manufacturing a flexible circuit electrode array, comprising: a) depositing a metal trace layer containing a base coating layer, a conducting layer and a top coating layer on the insulator polymer base layer; b) applying a layer of photoresist on the metal trace layer and patterning the metal trace layer and forming metal traces on the insulator polymer base layer; c) activating the insulator polymer base layer and depositing a top insulator polymer layer and forming one single insulating polymer layer with the base insulator polymer layer; d) applying a thin metal layer and a layer of photoresist on the surface of the insulator polymer layer and selective etching the insulator layer and the top coating layer to obtain at least one via; and e) filling the via with electrode material. A layer of polymer is laid down. A layer of metal is applied to the polymer and patterned to create electrodes and leads for those electrodes. A second layer of polymer is applied over the metal layer and patterned to leave openings for the electrodes, or openings are created later by means such as laser ablation. Hence the array and its supply cable are formed of a single body. Alternatively, multiple alternating layers of metal and polymer may be applied to obtain more metal traces within a given width. The method provides an excellent adhesion between the polymer base layer and the polymer top layer and insulation of the trace metals and electrodes.

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 purpose of the present invention is to provide: a novel triazole silane compound and a method for synthesizing the same, and a silane coupling agent containing the triazole silane compound as a component; and a surface treatment solution, a surface treatment method, and a method for bonding two different materials, which use said triazole silane compound.

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.

An etchant for copper includes an acid and one or more compounds selected from the group consisting of an aliphatic noncyclic compound, an aliphatic heterocyclic compound and a heteroaromatic compound. The aliphatic noncyclic compound is a saturated aliphatic noncyclic compound (A) including only two or more nitrogen atoms as heteroatoms, and 2 to 10 carbon atoms. The aliphatic heterocyclic compound is a compound (B) including a five-, six-, or seven-membered ring having one or more nitrogen atoms as one or more heteroatoms constituting the ring. The heteroaromatic compound is a compound (C) including a six-membered heteroaromatic ring having one or more nitrogen atoms as one or more heteroatoms constituting the ring.

A microetching agent is an acidic aqueous solution containing an organic acid, cupric ions, and halide ions. The molar concentration of halide ion of the microetching agent is 0.005 to 0.1 mol/L. By bringing the microetching agent into contact with a copper surface, the copper surface is roughened. An average etching amount in the depth direction during roughening is preferably 0.4 μm or less. The microetching agent can impart on copper surfaces a roughened shape having excellent adhesiveness to resins and the like, even with a low etching amount.

A method for repairing a fine line is provided. Nano metal particles are filled in a defect of a circuit board. The nano metal particles in the defect are irradiated by a laser, or heated, such that the nano metal particles in the defect are metallurgically bonded to an original line of the circuit board. A surface of the circuit board is cleaned to remove residual nano metal particles on parts of the circuit board where metallurgical bonding is not performed, thereby completing line repairing of the circuit board.

A method for assembling components implementing includes a pre-treatment of the solder bumps allowing an assembly by fluxless and residue-free soldering. A first component carrying solder bumps is assembled with a second component carrying connectors. Beforehand, a pre-treatment of the components carrying solder bumps is carried out by contacting them with a pre-treatment liquid which makes their subsequent fluxless and residue-free soldering possible.

A method is described for method for patterning a metal layer interfaced with a transparent conductive film, in which the method comprises contacting a structure through a patterned mask with an etching solution comprising Fe.sup.+3 ions, wherein the structure comprises the metal layer comprising copper, nickel, aluminum or alloys thereof covering at least partially a transparent conductive film with conductive elements comprising silver, to expose a portion of the transparent conductive film. Etching solutions and the etched structures are also described.