Thickness dependent CARS measurement of polymeric thin films without depth-profiling.
Coherent anti-Stokes Raman scattering (CARS) microscopy is demonstrated to be a promising optical method for the characterization of polymer films with film thickness varying between 180 nm to 4300 nm. In case of PMMA films with a thickness of few hundreds of nanometers, the observed CARS signal was mainly associated with the interference effect of large nonresonant CARS field from glass substrate and the weak resonant field of PMMA. The dependence of resonant CARS intensity of PMMA film on film thickness is in good agreement with the theoretical prediction on a CARS field. The current work offers potential possibilities of noninvasive thickness measurement of polymeric thin film of thickness less than 180 nm by multiplex CARS microscopy without depth-profiling.
Choi
Dae Sik
DS
Division of Advanced Technology, Korea Research Institute of Standards and Science, Daejeon 305-340, Korea.
Jeoung
Sae Chae
SC
Chon
Byung-Hyuk
BH