A microcircuit board for use with integrated circuits includes at least one thin film land to which components are to be soldered. The land is divided into solderable and nonsolderable areas, and the amount of solder that is preliminarily applied to the land will be determined by the ratio of the solderable areas to the non-solderable areas.
Disclosed is a printed circuit board comprising a contact terminal, which prevents a poor contact and reduces a manufacturing cost, and an image forming apparatus having the same. The printed circuit board comprises a circuit part for controlling and processing an operation of electronic appliance, and a large-area contact terminal formed by a group of small-area terminals for electric connection with external device. The small-area terminals can be formed in various types, respectively having regular size and shape and being distanced a predetermined interval. Accordingly, unevenness of the large-area contact terminal surface caused by soldering is prevented since a plurality of small-area terminals constitute a unit contact terminal of over a predetermined size. Therefore, quality of contact with external terminal improves. Further, manufacturing cost is reduced, and the manufacturing process becomes simple.
A method of manufacturing a microcircuit board with a mechanical cut-out piece between the microcircuit and the board to limit stresses transmitted to the microcircuit. A blank of a network of conductors is created and the microcircuit is fixed in a container formed by shaping the blank, the microcircuit keeping the different parts of the network in position relative to each other and the module thus formed is installed in a cavity in the board by fixing the external connection areas onto the upper surface of the cavity.
A printed circuit board wherein a conductor pattern is printed on an insulating base, first solder resist layers are formed on the surface of the conductor pattern remaining lands which are for soldering thereon, second solder resist layers for prevention of bridging for preventing bridging of solder are formed at least at portions where the gap between the lands is narrow, and thereby electronic parts such as an IC can be reliably assembled on the printed circuit board.
A mounting structure for a semiconductor device which is mounted onto a metallic wiring layer formed on a surface portion of a metal printed circuit board, in which bonding portions defined by substantially square etched holes are formed in a portion of the metallic wiring layer contacting a bonding material interposed between the metallic wiring layer and the body of the semiconductor device.
