EUVL mask inspection using 193nm wavelength for 30nm node and beyond

We report inspection results of EUVL masks with 193nm wavelength tools for 30nm and 24nm half-pitch nodes. The dense line and space and contact pattern is considered to study inspection capability. The evaluation includes defect contrast variation depending on illumination conditions, defect types, and design nodes. We show many inspection images with various optic conditions. Consequently, the detection sensitivity is affected by contrast variation of defects. The detection sensitivity and wafer printability are addressed with a programmed defect mask and a production mask. With these results, we want to discuss the capability of current EUVL mask inspection tools and the future direction.