Abstract:
A method of making an insulated patterned layer of an electrically conductive metal includes the steps of: (i) applying a layer of a radiation-curable material (2) to a substrate (1); (ii) imagewise exposing the layer of radiation-curable material to radiation to thereby cure portions (2a) of the layer exposed to such radiation; and (iii) removing the portions (2b) of the layer not exposed to radiation by means of a suitable solvent to thereby produce upon the substrate a patterned layer of cured radiation-curable material; and subsequently introducing electrically conductive metal (4) into the depressions (tracks) in the patterned relief layer.
Abstract:
A circuit board includes at least one circuit-conductor layer (1, 4), a ground layer (2) and a power source layer (3) superposed in a multilayer form and each layer insulated through dielectric layers (5) therebetween. A heat conduction through inside of the circuit board is enhanced so that circuit chips (12) mounted on the circuit board can be cooled down to a level capable of operating normally. The circuit board can be formed to be compact. In order to enhance the heat transfer in the circuit board, at least one of the ground layer (2) and power source layer (3) is formed in a multilayer manner. It is preferable to form these layers at a thickness larger than that of the circuit-conductor layer (1, 4). Further, preferably, the pin (9, 11) of the chip (12) mounted on the board and at least one of the ground layers (2) and power supply layer (3) are connected to each other in such a manner as to enhance the heat conduction.
Abstract:
The specification described a process for making a plating mask 17, for use in printed wiring board fabrication, with greater precision and definition that has previously been possible. An insulative substrate 11 includes on one surface a thin metal film (13). The film is covered with a relatively thick first mask layer (16) which is selectively removed to expose portions of the metal film, which are in turn removed to expose portions of the insulative substrate (11). The exposed portions of the insulative substrate are covered with a relatively thick plating mask layer (17) which abuts against the first mask layer (16). The first mask layer is then removed, leaving the remaining plating mask layer as a patterned plating mask which is then used as a mask for deposited metal (19) which defines a printed circuit.
Abstract:
A method for the manufacture of a printing wiring board, which proves particularly useful as a printed coil, is characterized by the fact that in the work in process which has undergone the step for fomation of a conductor circuit and which has not undergone the step for separation of a plating resist, the plating resist and other insulating substratal material are separated for transfer from the surface of the substrate having the conductor circuit formed thereon. Since this method permits formation of an extremely thin insulating layer and a conductor circuit layer thicker than the insulating layer, it enables production of very thin printed wiring board and printed coil (8) having high circuit density in the surfaces of component layers as well as in the direction of superposition of component layers.
Abstract:
A wiring board which uses both conductor patterns and reflection members provided at gaps therebetween to suppress unevenness in the reflection rate so as to raise the overall reflection rate and provide a reflection function on the surface of the wiring board at the side where an electronic device is mounted; facilitates shaping of the reflection members, controlling of the thickness of the reflection members, and controlling of the surface shape of the reflection members so as to stabilize the reflection rate; and secures close contact between the reflection members and sealing members so as to improve reliability. The wiring board comprises a plurality of wiring layers provided with conductor patterns disposed on base members, and base members which electrically insulate the plurality of wiring layers. At the outermost wiring layer among the plurality of wiring layers, reflection members are formed on the portions of the base member where there are no conductor patterns, the surface of these reflection members and the surface of the conductor patterns are made level and the surface of the conductor patterns are exposed from the reflection members.