5. 세미나 초록 : Defect detection on device process is one of challenging application as semiconductor process is shrinking down below 50nm. Half size of process design rule and less than an hour is the requirements of defect detection in general. We will discuss about the history of wafer inspection and evolution of inspection tools in the semiconductor industry. On the other hand, full 3D structure EM simulation work is carrying out to understand and predict the challenging defects. We will discuss few example of simulation work comparison with real experimental data.