Different approaches to overcome existing limits in optical micro and nano metrology

摘要

Modern products are becoming more miniaturised, more complex and have an increasing number of functionalities. The critical dimensions of structures written in silicon are becoming considerably smaller than the wavelength of the applied light source and this trend is to be sustained for the coming years until the next-generation patterning using extreme UV is implemented. As the feature sizes are decreasing, so the theoretical and practical constraints of making them and ensuring their quality are increasing. The same holds true for other industrial branches such as machine construction and automotive engineering where the surface-quality requirements of critical components and the overall complexity of the products have dramatically grown over the past few years. Consequently, modern production and inspection technologies are confronted with a bundle of challenges. In this paper at first the mentioned challenges and the physical limitations are addressed. Afterwards some modern approaches are discussed such as active wave front control, model based metrology and intelligent sensor fusion. On example of the inspection of non-resolved semiconductor structures and micro components new practical ways to cope with the mentioned challenges are presented.