摘要:
A surface reformation method of a high polymer material irradiates an excimer-laser beam to only a predetermined area in which electronic parts and the like are temporarily immobilized by a liquid on a substrate which has a high polymer layer on the surface. The wettability of the liquid for temporary immobilization only with respect to the predetermined area is improved. After the electronic parts are temporarily immobilized on the substrate by using the method, the electronic parts can be durably soldered by fluxless reflow soldering.
摘要:
An input video signal is written into alternate field memories M1 and M2, according to a timing clock from an input video clock generator. A display video signal is alternately read from those field memories, according to a timing clock from a display video clock generator. In switching a read memory, an address observation circuit judges whether or not a read/write address passes by a write/read address, referring to the condition of reading and writing operations. In this event, the circuit makes a judgement, based on the lag between a vertical synchronizing signals of an input video signal and of a display video signal, and a change of the lag with time. If it is judged that one address will pass by the other, the same read/write memory is again accessed for reading/writing. With this arrangement, there is provided a circuit having a relatively simple structure for preventing a match of read and write addresses.
摘要:
A flexible film-like member having conductive metals filled in tapered holes extending through the thickness is positioned such that the holes of the member face to respective pad patterns on a circuit board on which bumps are to be formed, the conductive metals are then heated and fused so that they are joined and transferred to the pad patterns on the circuit board, and the film-like member is then removed by heating or cleaning liquid.
摘要:
The present invention provides a multistep electronic circuit device comprising a plurality of parts and elements mechanically or electrically bonded in sequence to each other and to a substrate with a plurality of solders, which comprises as the parts and elements the substrate, input and output pins and LSI chips, and optionally packages and a cooler bonded through multistep bonding, the bondings of the parts and elements including at least one CCB bonding and at least one sealing, the solders each having a lower melting point than the heatproof temperature of the part or element to be bonded with the solder, and one of the solders having a melting point of at least 10.degree. C. lower than that of the other solder used at the bonding step immediately before. The solders used are selected from Au10-15wt%Ge alloy (melting point: 356.degree.-450.degree. C.), Pb1-5wt%Sn alloy (melting point: 314.degree.-325.degree. C.), Pb10-13wt%Sn alloy (melting point: 270.degree.-300.degree. C.), Au20wt%Sn alloy (melting point: 280.degree. C.), Sn3-6wt%Sb alloy (melting point: 232.degree.-243.degree. C.), Sn2-8wt%Ag alloy (melting point: 221.degree.-235.degree. C.), Sn35-55wt%Pb alloy (melting point: 183.degree. -200.degree. C.) and Sn45wt%Pb18wt%Bi (melting point: 135.degree.-160.degree. C.).
摘要:
An electronic circuit device comprising an electronic part having a gold-plated connecting terminal arranged thereon connected through a solder to a circuit substrate on the predetermined connecting element thereof, in which the connecting terminal of the electronic part and the solder-connected portion of the circuit substrate are constituted by an alloy composition consisting of 1.0 to 8.0 wt. % of Ag, 0.1 to 6.0 wt % of Au and the balance of Sn, is provided. The device is made by using a solder for use in connecting a gold-plated connecting terminal which consists of 1.0 to 8.0 wt % of Ag and the balance of Sn and a method of connecting an electronic part having a gold-plated connecting terminal arranged thereon to a circuit substrate, which comprises the steps of placing the electronic part and the gold-plated connected terminal so as to face each other via a solder and then melting the solder to connect and fix the connecting terminal to the circuit substrate onto the predetermined element thereof, the composition of said solder consisting of 1.0 to 8.0 wt % Ag and the balance of Sn.
摘要:
An apparatus for connecting wiring patterns on a wiring board and leads of a parts to be mounted on the wiring board, via the solder provided between the leads and the patterns. The parts-connecting apparatus enables, especially, circuit elements of a high degree of, to be connected automatically with high reliability and accuracy by using solder through the steps of setting the wiring board in a predetermined position while pressing a surface thereof so as to remove the warp from the wiring board, fastening the leads of the part to the wiring patterns by a magnet provided on the lower surface of the wiring board, and heating the solder provided on the portions of the leads which are fastened to the wiring patterns.
摘要:
A machine for automatically wiring an insulated fine wire as thin as a hair on the printed circuit board of wiring patterns are set up between adjacent conductor printed circuit board to be applied with wirings is carried by an X-Y table which is movable in X and Y directions, and the X-Y table is moved in accordance with wiring sites. A wire guide unit, a bonding unit and a wire cutter unit mounted, above the X-Y table, to a head rotatably supported about an axis perpendicular to the X-Y table surface are rotated along with the head so as to be oriented in various directions an optical device is supported for optical monitoring of the operations from above along the rotational axis of the bonding head. The wire guide unit sequentially pays out the insulated fine wire onto the printed circuit board carried by the X-Y table, the bonding unit exposes the core of the payed-out insulated wire and fuses the wire for connection thereof to the conductor pad of the printed circuit board by heating and depressing the payed-out wire, and the wire cutter unit cuts away the wire after completion of wiring.
摘要:
A process for producing expandable thermoplastic resin beads which comprises suspending in an aqueous medium 20 to 70% by weight of a random copolymer of propylene and ethylene containing 1 to 10% by weight of ethylene and 99 to 90% by weight of propylene and 30 to 80% by weight of a vinyl aromatic monomer such as styrene, polymerizing the vinyl aromatic monomer in the presence of a polymerization catalyst to graft the vinyl aromatic monomer onto the backbone of the random copolymer and, optionally, adding a cross-linking agent, to form graft-copolymerized thermoplastic resin beads, and introducing a blowing agent into the thermoplastic resin beads. The resulting resin beads have excellent foamability and molding fusability, and a foamed shaped article having superior thermal stability can be prepared from these beads.