Plowing: Modifying Cells and Routing in 45 ° -Layouts

This paper describes a plowing procedure which moves and modifies cells and routing. The plow pushes aside all obstacles one by one, thus penetrating into the layout. The process leads to a compaction at the front side of the plow. The compaction is performed in accordance with the minimum spacing rules and with automatic jog insertion. Objects of the layout representation are cells, contacts, and wires. A wire is represented by a path of segments which lie in one of two layers, at angles of multiples of 45°. The generated blank space is used for adding new objects or resizing geometries.