Analysis on the influence of several parameters in physical resist models

As the physical resist model has many parameters, calibrating the parameters from the wafer data will be time-consuming. With the purpose of improving the efficiency of physical resist model calibration, it is necessary to reveal the sensitivity of these parameters to the results of developed resist. By choosing the line space with CD 45nm and immersion scanner as conditions, an evaluation function including CD value, sidewall angle, top loss and resist loss is established. Based on this evaluation function, the effects of ten parameters in post-exposure bake (PEB) and develop processes on the developed results are analyzed by changing the value of a single parameter each time; Then, a simple but comprehensive experimental scheme is designed by using the definitive screening design (DSD), and the effects of various parameters and their coupling terms on the developed results are analyzed. Finally, the sensitivity of these parameters is revealed.