| 摘要 |
PURPOSE:To enable to perforate all through holes at the same etching time and to simplify works by a method wherein the through holes are standardized in small units of the same shape, and the total of their circumferential length is constituted in such a manner that it will become almost the same as or more of the circumferential length of the through holes before standardization. CONSTITUTION:The lower part of the metal wiring layer 5 of the second layer (the upper layer) is connected to the metal wiring layer 3 of the first layer (the lower layer) through the two through holes 7 perforated on an insulating layer 4. The total of the circumferential length of the two through holes is to be set almost same as or longer than their circumferential length. According to an experimental graph, the resistance R of the through holes are in the relation of RsimilarS<alpha> (alpha--0.4) with their area S, and this indicates that the resistance R is determined by the circumferential length of the through hole, instead of the area S of the through hole. |
