Method Development for Measuring Procedures for the In-Process-Characterisation of Sub-100-nm-Structures

• Applicant: Professor Dr.-Ing. Gert Goch
• Subject Area: Production Systems, Operations Management, Quality Management and Factory Planning
• Term: from 2014 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 254132876

Microtechnology and nanotechnology belong to the economic areas with the highest growth forecasts. In recent times, particularly in the area of the coating technologies, an increasing number of applications are on route to mass production. However, one of the largest remaining challenges is the realisation of an adequate process control. From this fact a rising demand for suitable in-process measuring procedures results. Theoretical examinations show that scattered light distributions principally contain information about existing nanostructures of the illuminated surfaces. Due to the fast, integral and contactless data acquisition, scattered light measuring procedures are predestined for in-process measurements of nanostructured systems. Unfortunately, the inverse problem cannot easily be solved because it is not possible to trace back to the underlying structures or to process deviations from the measured scattered light distributions. A first approach to solve this problem by rigorous light scattering simulations was examined in the DFG Priority Program SPP1327. Current research results show that the development of scattered light measuring procedures based on simulations is principally possible.The aim of this project is the realisation of a methodology for the development of scattered-light-based in-process measuring procedures for arbitrary nanostructured surfaces. This methodology shall result from the findings from three technical applications. In the first year of the research funding, an in-process measuring procedure for global stochastic defects is to be realized which is based on the preliminary investigations. The knowledge gathered with this system will be used as base for the development of the methodology. In the second year the planned characterisation of local occurring defects is related with a substantially higher measuring effort. The finally regarded deterministic defects represent the largest challenge in both areas: the technical realisation and the knowledge integration into the methodology. Stochastic effects induced by the surface roughness dominate, therefore there are no obvious deviations to be expected in the scattered light distributions. Thus the requirements to the measuring technique and also to the algorithms are substantially higher.

• DFG Programme: Research Grants