Abstract:
A solder-precoated wiring board on which devices and component can be mounted at fine pitches and which can be manufactured with a high productivity. A solder layer on a conductor for connection of electronic components on the wiring board comprises an Sn thin film layer formed by, for example, Cu-Sn substitution reaction on the basis of forming a Cu-complex of thiourea, and a Pb-coated Sn layer made by forming an Sn film, forming Sn crystalline particles film by Sn disproportionating reaction based on selective deposition on the Sn film, and substituting Pb for at least part of the Sn crystalline particles by Sn-Pb substituting reaction on the basis of the ionization tendency. It is desirable to melt this solder layer, and then, cool it to form an alloyed layer.
Abstract:
A circuit substrate for mounting a semiconductor element comprises an aluminum-copper clad foil (8,9) laminated on a metallic base plate (1) by interposing an insulating layer (2), wherein the roughness in average of the surface in contact with the insulating layer of the aluminum-copper clad foil is in a range of from 0.5 µm to 50 µm.
Abstract:
Conductive patterns may be formed on the surface of thermally inefficient substrates by depositing a uniform layer of metal thereover whose upper surface is substantially UV absorbing followed by laser ablation of the deposited metal to leave the deposited metal only in the desired metal pattern. Thermally efficient substrates (10) may be rendered thermally inefficient by the deposition of a thermally inefficient material thereon. That thermally inefficient material may be either electrically insulating or a metal. A two layer metallization comprising a first, thermally inefficient reactive metal (22) and a second UV absorbing metal (24) is preferred. When disposed on a thermally inefficient substrate, this two layer metallization ablates reactively as the two layers burn off together. This laser ablation process substantially roughens the surface of polymer dielectrics and may be used to repair open traces in printed circuit structures.
Abstract:
Conductive patterns may be formed on the surface of thermally inefficient substrates by depositing a uniform layer of metal thereover whose upper surface is substantially UV absorbing followed by laser ablation of the deposited metal to leave the deposited metal only in the desired metal pattern. Thermally efficient substrates (10) may be rendered thermally inefficient by the deposition of a thermally inefficient material thereon. That thermally inefficient material may be either electrically insulating or a metal. A two layer metallization comprising a first, thermally inefficient reactive metal (22) and a second UV absorbing metal (24) is preferred. When disposed on a thermally inefficient substrate, this two layer metallization ablates reactively as the two layers burn off together. This laser ablation process substantially roughens the surface of polymer dielectrics and may be used to repair open traces in printed circuit structures.
Abstract:
Matière améliorée pour plaquette de circuit imprimé composée d'une couche support, d'une couche résistance et d'une couche conductrice. La matière en question a une résistance d'environ 500 ohms par carré. La matière est obtenue en déposant la couche résistance par galvanoplastie sur la couche conductrice. La couche conductrice est activée de préférence avant que la couche résistance fasse l'objet d'un dépôt électrolytique. Cette couche conductrice est activée par contact avec un agent activant tel que le chromate de benzotriazole électrolytique ou un autre agent analogue. Un bain électrolytique préféré pour le dépôt électrolytique de la couche de résistance contient environ 0,5 parties par litre d'hypophosphite de nickel. Le bain électrolytique fonctionne à la température ambiante et est, en fait, indépendant de la température. Les plaquettes de circuit peuvent être fabriquées avec la matière en question par un processus ne comportant que deux opérations d'attaque.
Abstract:
Zur Wärmeabfuhr von auf einer Leiterplatte montierten Bauelementen ist auf die Leiterplatte (10) eine Kupferschicht (14) aufgebracht und auf diese Kupferschicht (14) eine Schicht (16) aus Reinaluminium aufgavanisiert. Die Leiterplatte (10) ist auf beiden Seiten mit Kupfer- und Reinaluminiumschichten (14,16) versehen, wobei die Bauelemente (12) jeweils auf einer solchen Kupfer- und Reinaluminiumschicht montiert sind. Die Leiterplatte (10) weist im Bereich der Bauelemente (12) Bohrungen (22) auf. Die Kupfer- und Reinaluminiumschicht (14, 16) erstreckt sich über die Innenwandung der Bohrung (22), so daß eine Verbindung (24) zwischen der mit dem Bauelement (12) in Kontakt befindlichen Kupfer- und Reinaluminiumschicht (14,16) und der Kupfer- und Reinaluminiumschicht auf der gegenüberliegenden Seite der Leiterplatte (10) hergestellt ist. Die aufgalvanisierte Reinaluminiumschicht (16) ist im Bereich der Bauteile (12) zur Erzielung einer planen Oberfläche mechanisch bearbeitet. In der Kupfer- und Reinaluminiumschicht (14,16) sind Bereiche (18) ausgespart, in denen Lötanschlüsse (20) und Leiterbahnen angeordnet sind.
Abstract:
A method of producing a printed circuit comprising printing a planting resist onto the clean surface of a layer of electrically conductive material on at least one side of a substrate so as to leave exposed only the required track areas of the surface; electroplating over the track areas a metal alloy, preferably a palladium/nickel alloy, which will act as an etch resist for the underlying electrically conductive material, which has good solderability, which has a melting point higher than 250 °C, and which will provide a base for gold plate, removing the plating resist; and removing the layer of electrically conductive material from the non-track areas by etching.
Abstract:
The invention provides processes for the manufacture of conductive transparent films and electronic or optoelectronic devices comprising same.
Abstract:
A substrate (SUB) includes a base substrate (BS), and a pad (PD) at one side of the base substrate (BS), wherein the pad (PD) comprises: a first conductive pattern (CP1) on the base substrate (BS), an insulating layer (PIL) including a plurality of contact holes exposing a portion of the first conductive pattern (CP1), and second conductive patterns (CP2) separately provided on the insulating layer (PIL) and connected to the first conductive pattern (CP1) through the plurality of contact holes, wherein side surfaces of the second conductive patterns (CP2) are exposed.