An Interactive Graphics System for the Design of Integrated Circuits

IGS (Interactive Graphics System) is a computer design aid specifically developed for the layout of integrated circuits. User specification of process information makes the system process-independent while retaining the features which make it a useful layout tool. The ability to place interconnect on a coarse grid greatly diminishes the chances of misalignment. Automatic, incremental checking of cell-to-cell, cell-to-component, and component-to-component spacing reduces the number of design rule violations. Rudimentary forms of topology verification are provided in the ability to trace electrical connectivity.