A contact and via Placement Algorithm for CMOS Analog Circuits Routing

Area routing based on gridless model is widely used in analog layout.Since there is no grid in the routing process,the router needs to decide the proper position where contact or via will be placed for connecting different routing layers.To solve this problem,we propose an algorithm to quickly and accurately find the maximum internal connecting rectangle in a Manhatten Polygon.Such an algorithm helps to enhance the routing quality and reduce the routing time.