| 摘要 |
1,234,314. Soldering. INTERNATIONAL BUSINESS MACHINES CORP. 20 Aug., 1969 [3 Sept., 1968], No. 41442/69. Heading B3R. [Also in Divisions H1 and H2] In a double-sided printed circuit having signal lines (not shown) formed on one side of a flexible substrate and a conductive ground plane 13 formed on the other side of the substrate, terminal pads 22 are connected to ground plane 13 by narrow bridge portions 23, 24, so that when terminal posts (not shown) are located in holes 27 in the substrate and terminals pads 22 and soldered, heat is substantially not transmitted to the ground plane 13 or to adjacent soldered joints so as to adversely affect bonding or damage the substrate. As described, the substrate is a flexible polyimide having a Cu cladding bonded to both sides thereof by a modified epoxy adhesive. Signal lines, terminal pads and bridge portions are formed by photoetching; holes are drilled through the assembly where required; and a layer of Cu is electroless-plated over the conductors and hole-walls. Terminal posts are connected to the signal lines by being inserted in holes 16 extending from terminal pads (not shown) integral with the signal lines to isolated terminal pads 17 etched out of ground plane 13, and soldered therein. Similarly, the terminal posts for terminal pads 22 are soldered in holes extending from isolated terminal pads (not shown) etched out on the signal line side of the circuit. Insulating layers are stuck over the signal lines and ground plane layers. |
