The whole solution space of the polymorphic travelling salesman problem(PTSP) could reach up to (N!)*(2^N) in lithography machine scan route planning, which is 2^N larger than normal TSP solution space. Here, N stands for the number of scan fields, and 2 means that it could have either plus(+) or minus(-) scan direction. Scan order and scan direction of scan fields should be determined simultaneously by solving PTSP. The challenge is that PTSP solution space expands rapidly with the increase in the number of scan fields. To find PTSP global optimal solutions more efficiently, a hybrid optimized evolutionary algorithm is proposed in this paper. Extended mathematical definitions on PTSP under different constraints are also described. Experiment results on classical 96 scan fields wafer layout are given, which shows the efficiency and improvements of our proposed algorithm compared with other algorithms listed in this paper.