Siefke, T.T.SiefkeRojas Hurtado, C.B.C.B.Rojas HurtadoDickmann, J.J.DickmannDickmann, W.W.DickmannKäseberg, T.T.KäsebergMeyer, J.J.MeyerBurger, S.S.BurgerZeitner, U.U.ZeitnerBodermann, B.B.BodermannKroker, S.S.Kroker2022-03-062022-03-062020https://publica.fraunhofer.de/handle/publica/26562610.1364/OE.3960442-s2.0-85089132024We demonstrate the retrieval of deep subwavelength structural information in nano-optical polarizers by scatterometry of quasi-bound states in the continuum (quasi-BICs). To this end, we investigate titanium dioxide wire grid polarizers for application wavelengths in the deep ultraviolet (DUV) spectral range fabricated with a self-aligned double-patterning process. In contrast to the time-consuming and elaborate measurement techniques like scanning electron microscopy, asymmetry induced quasi-BICs occurring in the near ultraviolet and visible spectral range provide an easily accessible and efficient probe mechanism. Thereby, dimensional parameters are retrieved with uncertainties in the sub-nanometer range. Our results show that BICs are a promising tool for process control in optics and semiconductor technology.endeep ultravioletscanning electron microscopysemiconductor device manufacturestructural information620621journal article