According to an embodiment of the present invention, a substrate for a printed circuit board, the substrate including a resin film and a metal layer deposited on at least one surface of the resin film, includes a modified layer on the surface of the resin film on which the metal layer is deposited, the modified layer having a composition different from another portion, in which the modified layer contains a metal, a metal ion, or a metal compound different from a main metal of the metal layer. The content of a metal element of the metal, the metal ion, or the metal compound on a surface of the modified layer is preferably 0.2 atomic % or more and 10 atomic % or less.

A surface finish for a printed circuit board (PCB) and semiconductor wafer includes a nickel disposed over an aluminum or copper conductive metal surface. A barrier layer including all or fractions of a nitrogen-containing molecule is deposited on the surface of the nickel layer to make a barrier layer/electroless nickel (BLEN) surface finish. The barrier layer allows solder to be reflowed over the surface finish. Optionally, gold (e.g., immersion gold) may be coated over the barrier layer to create a nickel/barrier layer/gold (NBG) surface treatment. Presence of the barrier layer causes the surface treatment to be smoother than a conventional electroless nickel/immersion gold (ENIG) surface finish. Presence of the barrier layer causes a subsequently applied solder joint to be stronger and less subject to brittle failure than conventional ENIG.

A manufacturing method of a substrate structure including vias includes the following steps. A substrate is provided, wherein a material of the substrate includes polyimide. An etching stop layer is formed on the substrate, wherein the etching stop layer covers two opposite surfaces of the substrate. A patterned process is performed on the etching stop layer to form a plurality of openings exposing a part of the substrate. An etching process is performed on the substrate to remove the part of the substrate exposed by the openings and form a plurality of vias.

A printed circuit board according to an embodiment of the present invention includes a base film having an insulating property and a conductive pattern disposed on at least one surface of the base film. The conductive pattern includes a copper particle bond layer which is fixed to the base film, and a lightness L* of a conductive pattern non-formed region of the base film is 60 or less. The base film may include a modified layer on one surface side thereof.

In some embodiments, methods include drilling one or a plurality of PTHs with any industrial grade drill to fabricate holes with positive etch back, flooding the PTHs with a dilute solution of an acrylate monomer/oligomer containing an appropriate level of peroxide initiator, polymerizing the acrylate, and then rising the PTHs with the solvent used in the formulation of the acrylate material. In one embodiment, the printed circuit board may include a substrate comprising a plurality of metal layers separated by a plurality of insulating layers; a plurality of plated through holes formed in the substrate, each plated through hole comprising: recesses formed at each insulating layer, copper lands between the recesses, a polymer coating in each recess, and a metal layer lining the plated through hole.

A base film for a printed circuit board according to an embodiment of the present invention is a base film for a printed circuit board, the base film containing a polyimide as a main component. A ratio of a peak intensity around a wave number of 1705 cm.sup.1 to a peak intensity around a wave number of 1494 cm.sup.1 in an absorption intensity spectrum of a surface of the base film, the spectrum being measured at an angle of incidence of 45 by total reflection infrared absorption spectroscopy, is 0.50 or more and 1.10 or less. A substrate for a printed circuit board according to an embodiment of the present invention includes the base film for a printed circuit board and a metal layer stacked on the surface of the base film for a printed circuit board.

A connection substrate includes a ceramic substrate with a through hole therein and a through conductor provided in the through hole and having first main surface and a second main surface. The through conductor includes a metal porous body having first open pores communicating with the first main surface, and second open pores communication with the second main surface, first glass phases provided in the first open pores, respectively, second glass phases formed in the second open pores, respectively, first spaces provided in the first open pores, respectively, and second spaces provided in the second open pores, respectively. The first spaces are closed spaces which do not communicate with the first main surface. The second spaces are open spaces communicating with the second main surface.

The ampholytic surfactants show the nature of anionic surfactants in an alkaline region and the nature of cationic surfactants in an acidic region. As described below, the pretreatment solution of the present invention may preferably indicate alkalinity of pH 8.5 or higher, and therefore, it exhibits the nature of cationic surfactants by the use of ampholytic surfactants. As the ampholytic surfactants, those disclosed in JP 2011-228517 A can be used.

An object is to provide a laminated polyimide substrate, and a method for the production thereof, in which various properties are ensured and/or provided by effectively controlling changes over time under stringent conditions, while ensuring sufficient adhesion between a polyimide film and metal layer. A laminated polyimide substrate comprises a polyimide layer, an alkali-treated layer derived from the polyimide layer, and a metal layer, arranged in that order, wherein the alkali-treated layer contains an anionic functional group, and is a laminated structure having a layer containing a metal catalyst arranged on the metal layer side and a layer containing a complex of the metal catalyst arranged on the polyimide layer side.

In a substrate like a printed circuit board comprising an insulator and a copper layer laminated on part of the insulator, said insulator outer surface and said copper layer outer surface are simultaneously subjected to a process (1) comprising treatment with an alkali metal hydroxide solution, a process (2) comprising treatment with an alkaline aqueous solution containing an aliphatic amine, a process (3) comprising treatment with an alkaline aqueous solution having a permanganate concentration of 0.3 to 3.5 wt % and a pH of 8 to 11, a process (4) comprising treatment with an acidic microemulsion aqueous solution containing a thiophene compound and an alkali metal salt of polystyrenesulphonic acid, and a process (5) comprising copper electroplating, which are implemented sequentially.