Abstract:
A photosensitive resin composition which, when exposed to light through a photomask and then developed, can form a pattern comprising a polyimide film having a thickness of 20 μm or larger with high resolution; and a use of the composition, in particular, a method of forming a pattern comprising the polyimide film. The photosensitive resin composition comprises (a) a poly(amic acid), (b) a specific 1,4-dihydropyridine derivative, and (c) a specific imide acrylate compound.
Abstract:
There are provided a circuit-forming substrate comprising a long stainless steel foil having formed on one surface or both surfaces thereof a polyimide resin layer wholly or partially, and a circuit substrate formed by using the circuit-forming substrate, wherein a conductor layer is finely patterned on the circuit-forming substrate. The circuit-forming substrate sufficiently satisfies low cost, high density and high reliability, scarcely causes warping of the substrate itself, and has excellent workability.
Abstract:
A wired circuit board includes a metal supporting board, an insulating layer formed on the metal supporting board, a conductive pattern formed on the insulating layer and having a plurality of wires, and a semiconductive layer formed on a surface of the insulating layer exposed from the conductive pattern so as to be in contact with the conductive pattern. The insulating layer is formed with a groove exposing the metal supporting board between at least two adjacent wires, and the semiconductive layer is in contact with the metal supporting board in the groove.
Abstract:
The invention provides a wired circuit board that can prevent deterioration of a conductive pattern and short-circuiting of the conductive pattern. The wired circuit board is presented herein in the form of a suspension board with circuit which comprises an insulating base layer formed on a metal supporting board, a conductive pattern formed on the insulating base layer, a metal oxide layer formed on a surface of the conductive pattern and on a surface of the insulating base layer by sputtering, and an insulating cover layer, formed on the metal oxide layer, to cover the conductive pattern. According to this suspension board with circuit, since the metal oxide layer to cover the conductive pattern is formed by the sputtering, the metal oxide layer can be formed with a uniform thickness. Hence, the metal oxide layer can fully function as a barrier layer to the conductive pattern and, accordingly, deterioration of the conductive pattern and the short-circuiting of the conductive pattern can be prevented effectively.
Abstract:
A wired circuit board that can remove static electricity not only from an insulating base layer and an insulating cover layer but also from a terminal portion, to effectively prevent an electronic component mounted from being damaged by static electricity and also prevent stripping of a semi-conductive layer. In a suspension board with circuit including an insulating base layer formed on a metal supporting board, a conductive pattern formed on the insulating base layer, and an insulating cover layer, formed on the insulating cover layer, to cover the conductive pattern and form an opening, semi-conductive layer is formed in succession on an upper surface of the insulating base layer covered with the insulating cover layer, on a lateral side surface and an upper surface of the conductive pattern, and on a lateral side surface of the insulating base layer adjacent to the metal supporting board.
Abstract:
A wired circuit board and a producing method thereof are provided which can precisely form an insulating layer and reduce transmission loss with a simple layer structure and also features excellent long-term reliability by preventing the occurrence of an ion migration phenomenon between a ground layer and a positioning mark layer, and the insulating layer to improve the adhesion therebetween and the conductivity of a conductor. A metal supporting board is prepared and a first metal thin film is formed on the metal supporting board. A resist is formed in a pattern and a ground layer and a positioning mark layer are formed on the first metal thin film exposed from the resist at the same time. A second metal thin film is formed over the ground layer and the positioning mark layer, then the resist is removed. An insulating base layer is formed on the first metal thin film including the upper surface of the second metal thin film, thereafter, a conductive pattern is formed on the insulating base layer.
Abstract:
A suspension board with circuit that can allow precise adjustment of flotation (flotation angle) of even a small-sized slider to a magnetic disc even when the outrigger portions are reduced in rigidity. A gimbal portion of the suspension board with circuit is formed by a tongue portion for mounting a magnetic head thereon, and outrigger portions provided at both sides of the tongue portion, and an opening is formed in the insulating cover layer 5 so that the conductor layer can be exposed therefrom in the outrigger portions. This can allow reduction in rigidity of the outrigger portions, and as such can allow precise adjustment of flotation (flotation angle) of the slider to the magnetic disc even when a small-sized slider is mounted on the gimbal portion.
Abstract:
An area 5 for mounting a magnetic head is formed on a metal board 1, a conductive layer 4 is formed as a circuit pattern via an insulation layer 2 interposed outside this area and up to a metal board 1. A pattern end 4 to be a connection terminal for connection with the terminal of the magnetic head is formed on the circuit pattern, an end face 4a of the pattern end 4 is aligned with an end face 2a of the insulation layer 2 directly beneath it or protruded in the terminating direction from the end face 2a, thereby providing a structure preventing irradiation of a laser beam on the insulation layer 2.
Abstract:
A wired circuit board is provided which can reduce transmission loss with a simple layer structure and also features excellent long-term reliability by preventing the occurrence of an ion migration phenomenon between a metal foil and an insulating layer to improve the adhesion between the metal foil and the insulating layer and the conductivity of a conductor. A metal supporting board is prepared and a first metal thin film is formed on the metal supporting board by sputtering or electrolytic plating. A metal foil is formed on the first metal thin film by electrolytic plating. A second metal thin film is formed over the metal foil and the metal supporting board by electroless plating or sputtering. An insulating base layer is formed on the second metal thin film. A conductive pattern is formed as a wired circuit pattern on the insulating base layer. An insulating cover layer is formed on the insulating base layer to cover the conductive pattern.
Abstract:
A wired circuit board that can provide a reduced transmission loss and an improved adhesion strength between a metal suspension board and a metal foil with a simple laminar structure, thereby ensuring improved long-term reliability. The wired circuit board 1 comprises a metal suspension board 2, a thin metal film 3 formed on the metal suspension board 2 by sputtering or by electrolytic plating, a metal foil 4 formed on the thin metal film 3 by electrolytic plating, an insulating base layer 5 formed on the metal foil 4 and the metal suspension board 2, and a conductive pattern 6 formed on the insulating base layer 5 as a wired circuit pattern. The wired circuit board 1 may include an insulating cover layer 7 formed on the insulating base layer 5 to cover the conductive pattern 6.