Development of New Inspection System with Novel Pem for Euv Pattern Masks and Its Performance Evaluation

In order to realize EUV mask pattern defect inspection in 16nm node, we have developed a new inspection system assembled with a new optical system on novel projection electron microscopy (PEM) and a new mask handling and imaging system, e. g., a high precision stage, an imaging detector, an image processing system, and so. on. This inspection system enables us to make the inspection in high resolution and high speed as compared to conventional DUV and EB inspection systems. In this paper, we describe the performance evaluation as concerning to the acquisition operation on the assembled new inspection system with 16nm node EUV mask: 1) Still and TDI image acquisition, and 2) die-to-die inspection. The results show that the new inspection system operations in the still and TDI modes are in much feasibility in stable image acquisition, and in the die-to-die inspection are capable to execute the die-to-die inspection for 1Xnm EUV mask.