| 摘要 |
The unit comprises: a ceramic substrate 9 with a plurality of input/output terminals 1 on its lower surface and at least one supply layer 5 having a plurality of conducting lines, and a plurality of metallised through holes 4 between its lower and upper surfaces in order to connect each of the terminals, a plurality of signal wiring layers 6 on the topside of the substrate having a plurality of chips 3 on the topside of the upper layer of the signal wiring layers for mounting and connecting circuit elements; a plurality of spare chips 7 on the surface of the upper signal wiring layer for connecting repair wires; a plurality of spare terminals 8 on the underside of the substrate; and a means of spare wiring across the substrate and the signal wiring layers in order to connect the chips and the spare terminals. …<IMAGE>… |
