An enhanced global router with consideration of general layer directives

In this paper we study a global routing problem that considers not only overflow and wirelength but also layer directives. A layer directive is often given to a timing-critical net for meeting target performance, and it specifies a range of consecutive layers on which the net should be routed. Unlike a previous work that focuses only on a restricted set of layer ranges, our problem allows arbitrary layer ranges to be specified. We present a global router which enhances an academic router by employing techniques to take general layer directives into account during two-dimensional (2D) routing and layer assignment. The experiment results show that our global router can produce encouraging solutions for all test cases.