There is provided a roughened copper foil which can significantly improve adhesion to an insulating resin and reliability (e.g., hygroscopic heat resistance). The roughened copper foil of the present invention has at least one roughened surface having fine irregularities composed of acicular crystals, wherein the entire surface of the acicular crystals is composed of a mixed phase of Cu metal and Cu.sub.2O.

To provide an electronic circuit production method using 3D layer shaping capable of producing an electronic circuit having improved electrical properties and mechanical properties by utilizing characteristics of a fluid containing a metal particle by selectively using the fluid containing the metal particle. The electronic circuit production method using 3D layer shaping, the method including a wiring forming step of forming a wiring by applying a fluid containing a nano-sized metal nanoparticle on an insulating member and curing the applied fluid containing the metal nanoparticle; and a connection terminal forming step of forming a connection terminal electrically connected to the wiring by applying a fluid containing a micro-sized metal microparticle and curing the applied fluid containing the metal microparticle.

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.

Disclosed are: a microetching agent which can form roughened shapes less affected by differences in the crystallinity of the copper and with which roughened shape excellent in terms of adhesiveness to resins, etc. can be formed on either electrolytic copper or rolled copper; and a method for producing a wiring board which includes a step of roughening a copper surface using the microetching agent. In the present invention, the microetching agent for copper is an acidic aqueous solution containing an inorganic acid, a cupric ion source, a halide ion source, and a polymer. The polymer has a functional group containing a nitrogen atom. It is preferable that the microetching agent contain a sulfate ion source.

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.

Tamper-proof electronic packages and fabrication methods are provided including an enclosure enclosing, at least in part, at least one electronic component within a secure volume, a two-phase dielectric fluid within the secure volume, and a tamper-respondent detector. The tamper-respondent detector monitors, at least in part, temperature and pressure of the two-phase dielectric fluid. In operation, the two-phase dielectric fluid deviates from an established saturation line of the two-phase dielectric fluid within the secure volume with an intrusion event into the secure volume, and the tamper-respondent detector detects, from the monitoring of the temperature and pressure of the two-phase dielectric fluid, the deviation from the established saturation line, and thereby occurrence of the intrusion event.

The invention provides transient devices, including active and passive devices that electrically and/or physically transform upon application of at least one internal and/or external stimulus. Materials, modeling tools, manufacturing approaches, device designs and system level embodiments of transient electronics are provided.

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.

The invention provides transient devices, including active and passive devices that physically, chemically and/or electrically transform upon application of at least one internal and/or external stimulus. Incorporation of degradable device components, degradable substrates and/or degradable encapsulating materials each having a programmable, controllable and/or selectable degradation rate provides a means of transforming the device. In some embodiments, for example, transient devices of the invention combine degradable high performance single crystalline inorganic materials with selectively removable substrates and/or encapsulants.

A surface treatment solution for copper and copper alloy surfaces comprising an acid and an oxidising agent selected from the group consisting of hydrogen peroxide, metal peroxides, metal superoxides and mixtures thereof, at least one source of chloride ions and at least one source of bromide ions. The surface treatment solution is particularly useful in the manufacturing of printed circuit boards, IC substrates and other electronic appliances.