Abstract: A multilayer interconnection substrate includes a resin laminated structure in which plural build-up layers are laminated, each of the plural build-up layers comprising an insulation layer and an interconnection pattern, and first and second solder resist layers provided on a top surface and a bottom surface of the resin laminated structure, wherein each of the first and second solder resist layers includes a glass cloth.

Abstract: The circuit board comprises a through-hole via which is formed in a through-hole passed through a substrate and includes a via portion electrically connected to a part of a plurality of interconnection layers at the inside wall of the through-hole and a pad portion formed on a surface of the substrate in a region surrounding the through-hole and is connected to the via portion. In the circuit board, an opening is formed for passing through the through-hole via out of connection with a constant-voltage interconnection layer in the region where the through-holes is formed. The constant-voltage interconnection layer is the interconnection layer nearest to the pad portion, and an outer diameter of the pad portion is larger than a diameter of the opening formed in the constant-voltage interconnection layer, whereby a capacitor including the pad portion and the constant-voltage interconnection layer as a pair of electrodes is formed.

Abstract: An inexpensive multilayer wiring circuit board capable of conducting high frequency switching operation on the circuit while the generation of high frequency noise is being suppressed by reducing the inductance of the circuit in provided. A multilayer wiring circuit board comprising: an uppermost layer designated as a first layer on which parts are mounted; a second layer on which one of a ground layer and an electric power source layer is arranged; a third layer on which the other is arranged; and an insulating layer arranged between the ground layer and the electric power source layer. A resin layer having a thermoplastic adhesion property on both faces is used as material of the insulating layer arranged between the electric power source layer and the ground layer.

Abstract: The present invention is aimed to provide a head suspension having a high resonant frequency, high shock resistance and low rigidity, which greatly contributes to an improvement of a magnetic disk apparatus. In an oscillation-type actuator, at least a part of a spring arm of the head suspension having a data reading/writing head slider 1 is made of an anisotropic layer whose rigidity varies in accordance with a direction. In this case, the anisotropic layer is laminated so that the high rigidity modulus orientation direction is different according to layer.

Abstract: An inexpensive multilayer wiring circuit board capable of conducting high frequency switching operation on the circuit while the generation of high frequency noise is being suppressed by reducing the inductance of the circuit in provided. A multilayer wiring circuit board comprising: an uppermost layer designated as a first layer on which parts are mounted; a second layer on which one of a ground layer and an electric power source layer is arranged; a third layer on which the other is arranged; and an insulating layer arranged between the ground layer and the electric power source layer. A resin layer having a thermoplastic adhesion property on both faces is used as material of the insulating layer arranged between the electric power source layer and the ground layer.

Abstract: The present invention is aimed to provide a head suspension having a high resonant frequency, high shock resistance and low rigidity, which greatly contributes to an improvement of a magnetic disk apparatus. In an oscillation-type actuator, at least a part of a spring arm of the head suspension having a data reading/writing head slider 1 is made of an anisotropic layer whose rigidity varies in accordance with a direction. In this case, the anisotropic layer is laminated so that the high rigidity modulus orientation direction is different according to layer.

Abstract: An inexpensive multilayer wiring circuit board capable of conducting high frequency switching operation on the circuit while the generation of high frequency noise is being suppressed by reducing the inductance of the circuit in provided. A multilayer wiring circuit board comprising: an uppermost layer designated as a first layer on which parts are mounted; a second layer on which one of a ground layer and an electric power source layer is arranged; a third layer on which the other is arranged; and an insulating layer arranged between the ground layer and the electric power source layer. A resin layer having a thermoplastic adhesion property on both faces is used as material of the insulating layer arranged between the electric power source layer and the ground layer.

Abstract: A resin composition comprising an epoxy group-containing cycloolefin resin and a crosslinking agent is provided. More specifically, a resin composition comprising an epoxy group-containing thermoplastic norbornene resin obtained by introducing epoxy groups into a thermoplastic norbornene resin, and as the crosslinking agent, a curing agent for epoxy resins or a photoreactive substance is provided. The resin composition is suitable for use as an insulating material.

Abstract: A resin composition comprising an epoxy group-containing cycloolefin resin and a crosslinking agent is provided. More specifically, a resin composition comprising an epoxy group-containing thermoplastic norbornene resin obtained by introducing epoxy groups into a thermoplastic norbornene resin, and as the crosslinking agent, a curing agent for epoxy resins or a photoreactive substance is provided. The resin composition is suitable for use as an insulating material.

Abstract: Disclosed herein is a pattern forming process comprising the steps of coating a substrate with a photosensitive resin composition comprising a polyamic compound having, at each terminal thereof, an actinic ray-sensitive functional group which has substituent groups each having a photopolymerizable carbon-carbon double bond, a photosensitive auxiliary having a photopolymerizable functional group, a photopolymerization initiator, and a solvent to form a film; subjecting the film to pattering exposure; and then developing the thus-exposed film with an alkaline developer or alkaline aqueous solution.

Abstract: A resin composition comprising an epoxy group-containing cycloolefin resin and a crosslinking agent is provided. More specifically, a resin composition comprising an epoxy group-containing thermoplastic norbornene resin obtained by introducing epoxy groups into a thermoplastic norbornene resin, and as the crosslinking agent, a curing agent for epoxy resins or a photoreactive substance is provided. The resin composition is suitable for use as an insulating material.

Abstract: Provided are photosensitive resin compositions comprising a polyamic compound having, at each terminal thereof, a specific actinic ray-sensitive functional group which has substituent groups each having a photopolymerizable carbon-carbon double bond, a photosensitive auxiliary having a photopolymerizable functional group and a solvent. The photosensitive resin compositions of the invention are excellent in resist properties such as sensitivity and good in storage stability and can provide a film small in residual stress.

Abstract: An interlayer connection wiring penetrating each of resin films constituting a multilayer circuit board and a surface wiring connected to the interlayer connection wiring are formed in predetermined positions on surfaces of each resin film. The resin films are laminated while being positioned so that the interlayer connection wiring of one of each adjacent pair of the circuit bases is superposed on a part of the surface wiring of the other, and are thereafter treated under a high-temperature and high-pressure condition to be combined with each other. If a resin film formed of a thermoplastic resin is adopted, the laminated resin films are combined by intermixing the interfaces of each adjacent pair of resin films. As the resin films shrink when the laminated resin films is cooled to ordinary temperature, a compressive force is applied to the contact surfaces of the interlayer connection wiring and the surface wiring.

Abstract: An etching process of a conductive layer in manufacturing polyimide multilayer printed wiring boards comprises the steps of dipping in an alkali aqueous solution for patterning the conductive layer, dipping in an acid aqueous solution for neutralizing the alkali residue, and washing with water thereby washing off the alkali residue. A curing process for each of polyimide layers is controlled so as to obtain a polyimide conversion ratio ranging between 60% and 100% after an initial curing process, and to obtain a polyimide conversion ratio close to 100% after formation of an uppermost polyimide layer.

Abstract: An excimer laser ablation processing for forming via holes in a resin film by irradiation of an excimer laser wherein, the emission of light caused during the decomposition of the resin during the processing is detected, its intensity is measured, and the endpoint of the processing is judged or a comparison is made of the positions of light emission and the design positions for processing to examine for the presence of defects. Provision is made of a means for measuring the intensity and a means for judging the endpoint of the processing from the changes in the intensity of light emission during the processing.