| 摘要 |
In consideration for the fact that a connection on the upper layers of an integrated circuit needs to access a lower layer to connect to, e.g., a transistor, at least one via on each layer is required below the top layer used by a connection for each pin. The vias (i.e., the connection structures between wiring planes within an integrated circuit) are arranged such that the number of wiring resources blocked on the lower layers is reduced. Various rules govern which vias are chosen. The main characteristic is to elect only a certain number of wiring channels appropriate for the vias on a single layer and then apply an optimization within the restricted elected wiring channels on that layer to select the most appropriate vias.
|
