Buffered tree refinement considering timing and congestion

In this paper, we present an algorithm to improve the congestion cost and even the timing of a given buffered tree. By decomposing a buffered tree into several components and selecting alternative positions to move the drivers of these components, we can use pre-computed look-up tables to reconstruct the buffered tree such that the congestion cost and even the timing can be improved, in our experiments, we used the buffered trees which were created by S. Dechu et al. (2004) as the testcases, and the results show that our algorithm can improve the congestion cost up to 34% and the timing up to 15.8%.