  In this work, we propose a new signal routing method for solving routing
problems that occur in the design process of semiconductor package substrates.
Our work uses a topological transformation of the layers of the package
substrate in order to simplify the routing problem into a problem of connecting
points on a circle with non-intersecting straight line segments. The circle,
which we call the Circular Frame, is a polygonal schema, which is originally
used in topology to study the topological structure of 2-manifolds. We show
through experiments that our new routing method based on the Circular Frame
competes with certain grid-based routing algorithms.
