To get a more efficient program for net routing design in VLSI physical design, a new mixed algorithm is presented by combining ant colonies algorithm and Tabu search algorithm for improving net routing design scheme in VLSI physical design. The models by considering different structure property such as two-terminal, multiple-terminal, multi-layers and gridless net routing are developed with introducing the proper parameters matching which can be obtained by computer experiments. The results show that the new algorithm can avoid the low convergence rate in the initial stage of basic ant colonies system. The efficiency of the Tabu-ant colonies is improved about 16.667%; meantime, the Tabu-ant colonies system can also avoid the local optimal solution effectively. It builds a basis for future work in solving multiple-terminal, multiple-layers and gridless net routing problems with high efficiency. 
Optimal approach on net routing for VLSI physical design based on Tabu-ant colonies modeling