Abstract: A metal-film forming method of the present invention includes a surface activation process of irradiating a laser beam to the surface of the base metal, thereby activating the surface of the basemetal, a noble-metal nanoparticle dispersion liquid coating process of coating the surface of the base metal with a noble-metal nanoparticle dispersion liquid, a solvent thereof, containing noble-metal nanoparticles in as-dispersed state, and a noble-metal nanoparticle sintering process of irradiating the laser beam to the noble-metal nanoparticle dispersion liquid coated on the surface of the base metal, thereby causing the noble-metal nanoparticles to be sintered. Further, a scudding press process of executing press forming of a base metal, and the metal-film forming process of applying noble-metal plating to the surface of the base metal are executed on the same line.

Abstract: An electronic device substrate is provided with a thin-plate core substrate; a metal electrode provided on the core substrate and electrically connected to an electrode of an electronic component to be packaged thereon; and an electrical insulation layer on which is mounted the electronic component, and which is provided to surround the metal electrode.

Abstract: An electronic device substrate is provided with a thin-plate core substrate; a metal electrode provided on the core substrate and electrically connected to an electrode of an electronic component to be packaged thereon; and an electrical insulation layer on which is mounted the electronic component, and which is provided to surround the metal electrode.

Abstract: A lead frame includes a base material, a reflection layer formed on a part of the base material, and a characteristic sustaining layer formed at least on the reflection layer to cover the reflection layer for sustaining a characteristic of the reflection layer by isolating the reflection layer from an outside. The reflection layer includes the characteristic to exhibit a predetermined reflectivity to light with a predetermined wavelength, and the characteristic sustaining layer prevents a decrease in the reflectivity of the reflection layer and transmits light reflected by the reflection layer.

Abstract: On both surfaces of an electric insulating material 1, a surface conductive layer 2A and a back surface conductive layer 2B are formed by transcription. Further, a via hole 5 penetrating through the surface conductive layer 2A and the electric insulating material 1 is provided. After forming a photosensitive plating resist pattern 14, the via hole 5 is filled with a copper plating filler 15, and the surface wiring layer 9A and the back surface wiring layer 9B are formed. Thereafter, the photosensitive plating resist pattern 14 as well as the surface conductive layer 2A and the back surface conductive layer 2B provided under the photosensitive plating resist pattern 14 are removed to fabricate a double-sided wiring board 11.

Abstract: An electronic device substrate is provided with a thin-plate core substrate; a metal electrode provided on the core substrate and electrically connected to an electrode of an electronic component to be packaged thereon; and an electrical insulation layer on which is mounted the electronic component, and which is provided to surround the metal electrode.

Abstract: A lead frame includes a base material, a reflection layer formed on a part of the base material, and a characteristic sustaining layer formed at least on the reflection layer to cover the reflection layer for sustaining a characteristic of the reflection layer by isolating the reflection layer from an outside. The reflection layer includes the characteristic to exhibit a predetermined reflectivity to light with a predetermined wavelength, and the characteristic sustaining layer prevents a decrease in the reflectivity of the reflection layer and transmits light reflected by the reflection layer.

Abstract: An electronic device substrate is provided with a thin-plate core substrate; a metal electrode provided on the core substrate and electrically connected to an electrode of an electronic component to be packaged thereon; and an electrical insulation layer on which is mounted the electronic component, and which is provided to surround the metal electrode.

Abstract: A wiring board which can realize a small and thin passive component such as solid condenser, resistor, coil, transistor or so on is provided. A wiring board which forms an electronic component by mounting a passive element, comprising an insulating board provided with an opening having predetermined pattern, a wiring formed with predetermined pattern on said insulating board, and an external terminal filled to said opening, connected with said wiring by said filling, and exposed to a bottom of said insulating board where said wiring is formed.

Abstract: A semiconductor device having a superior connection reliability is obtained by providing a buffer body for absorbing the difference of thermal expansion between the mounting substrate and the semiconductor element in a semiconductor package structure, even if an organic material is used for the mounting substrate. A film material is used as the body for buffering the thermal stress generated by the difference in thermal expansion between the mounting substrate and the semiconductor element. The film material has modulus of elasticity of at least 1 MPa in the reflow temperature range (200–250° C.).

Abstract: An electronic device substrate is provided with a thin-plate core substrate; a metal electrode provided on the core substrate and electrically connected to an electrode of an electronic component to be packaged thereon; and an electrical insulation layer on which is mounted the electronic component, and which is provided to surround the metal electrode.

Abstract: In a semiconductor device having a three-layered buffer layer comprising core layer 1 having interconnected foams such as a three-dimensional reticular structure and adhesive layers 2 provided on both sides of the core layer as a stress buffer layer between semiconductor chip 5 and wiring 4 to lessen a thermal stress generated between the semiconductor device and the package substrate, where a thickness ratio of the core layer 1 to total buffer layer is at least 0.2, the production process can be simplified by using such a buffer layer, thereby improving the mass production capacity and enhancing the package reliability.

Abstract: The object of the present invention is provide a semiconductor device in semiconductor package configuration, characterized by excellent connection reliability ensured by incorporating a buffer for absorbing differences in thermal expansion rate between a mounting substrate and a semiconductor element even when an organic material is used for a mounting substrate.

Abstract: In a semiconductor device having a three-layered buffer layer comprising core layer 1 having interconnected foams such as a three-dimensional reticular structure and adhesive layers 2 provided on both sides of the core layer as a stress buffer layer between semiconductor chip 5 and wiring 4 to lessen a thermal stress generated between the semiconductor device and the package substrate, where a thickness ratio of the core layer 1 to total buffer layer is at least 0.2, the production process can be simplified by using such a buffer layer, thereby improving the mass production capacity and enhancing the package reliability.

Abstract: A semiconductor device having a superior connection reliability is obtained by providing a buffer body for absorbing the difference of thermal expansion between the mounting substrate and the semiconductor element in a semiconductor package structure, even if an organic material is used for mounting substrate. A film material is used as the body for buffering the thermal stress generated by the difference in thermal expansion between the mounting substrate and the semiconductor element. The film material has modulus of elasticity of at least 1 MPa in the reflow temperature range (200-250° C.).

Abstract: A wiring board which can realize a small and thin passive component such as solid condenser, resistor, coil, transistor or so on is provided. A wiring board which forms an electronic component by mounting a passive element, comprising an insulating board provided with an opening having predetermined pattern, a wiring formed with predetermined pattern on said insulating board, and an external terminal filled to said opening, connected with said wiring by said filling, and exposed to a bottom of said insulating board where said wiring is formed.

Abstract: A structure of a semiconductor device of a chip scale package structure is provided. In the semiconductor device, the limitation to size reduction due to the bonding tool is small and the bonding pitch of the semiconductor chip can be reduced to 100 &mgr;m or less, and the chip shrink technique of a technique for lowering the cost can be employed and in connection with this compatibility among packages can be kept.

Abstract: In a semiconductor device having a three-layered buffer layer comprising core layer 1 having interconnected foams such as a three-dimensional reticular structure and adhesive layers 2 proved on both sides of the core layer as a stress buffer layer between semiconductor chip 5 and wiring 4 to lessen a thermal stress generated between the semiconductor device and the package substrate, where a thickness ratio of core layer 1 to total buffer layer is at least 0.2, the production process can be simplified by using such a buffer layer, thereby improving the mass production capacity and enhancing the package reliability.

Abstract: A semiconductor device having a superior connection reliability is obtained by providing a buffer body for absorbing the difference of thermal expansion between the mounting substrate and the semiconductor element in a semiconductor package structure, even if an organic material is used for the mounting substrate. A film material is used as the body for buffering the thermal stress generated by the difference in thermal expansion between the mounting substrate and the semiconductor element. The film material has modulus of elasticity of at least 1 MPa in the reflow temperature range (200-250° C.).

Abstract: A semiconductor device, comprising: a semiconductor chip having on its main plane a plurality of external electrodes each having a joining portion; an insulating substrate having a predetermined pattern of leads thereon and having no device hole for said semiconductor chip, each of said leads being provided with an inner lead having a joining portion which is joined through solder to a corresponding one of the joining portions of said external electrodes of said semiconductor chip to provide a joined portion; and a molding resin for sealing said joined portion including the solder, wherein the joining portion of the external electrode comprises a metal selected from the group consisting of gold and tin, the joining portion of the inner lead comprises a metal selected from the group consisting of gold and tin, provided that, when the metal constituting the joining portion of the external electrode is gold, the metal constituting the joining portion of the inner lead is tin, or vice versa, and the solder compri