EUV reflective coherent diffraction imaging system for wafer metrology

Abstract

Nanoscale non-destructive metrology is a key requirement in several steps of the manufacturing process of modern semiconductor devices. In particular, with the introduction of EUV lithography into the high-volume manufacturing, enabling further shrinking of feature sizes, metrology for future technology nodes will become increasingly challenging. Depending on the specific requirements and constraints of the metrology tasks, the choice of the measurement methods is critical, and sometimes limited. Conventional metrology techniques must be constantly adapted to keep up with the device scaling roadmap. To explore new and easily scalable methods for semiconductor wafer metrology, we developed the EUV reflective grazing-incidence nanoscope (REGINE). REGINE is a lensless nanoscope prototype that combines reflectometry, scatterometry and coherent diffraction imaging (CDI) in a single instrument. Being a lensless imaging system, it is compact, cost-effective, and free of lens-induced aberrations. In this work, we will present the REGINE system and the latest results of reflectometry, scatterometry and EUV pellicle transmission experiments.

EUV reflectometry and scatterometry for thin layer and periodic structure characterization

“…REGINE is a synchrotron-based instrument that is developed for thin film and grating characterization, along with coherent diffraction imaging (CDI) of patterned wafers. 9,10 Housed within a high vacuum chamber operating at the pressure of 10 −7 mbar, REGINE offers a comprehensive platform for advanced metrology tasks. Figure 1 provides an overview of the entire REGINE system.…”