DIELECTRIC PERMITTIVITY MAPPING WITH NON-CONTACT MICROWAVE PROBE FOR DIELECTRIC MATERIALS

摘要

The high frequency reflection intensity was measured for Al_2O_3 and SrTiO_3 substrates at room temperature using a non-contact microwave probe as a function of distance between sample and probe. The difference of reflection intensity for Al_2O_3 and SrTiO_3 substrates was observed in the region where the distance of 0.2mm between sample and probe, and it was caused from dielectric permittivities of samples. The reflection coefficient of sample was estimated in comparison with results of electromagnetic simulation using finite differential time domain method. The reflection intensity for Al_2O_3 and SrTiO_3 substrates was transformed to dielectric permittivity at reflection intensity minimum point. The in-plane reflection intensity mapping for Al_2O_3 substrate/Cu-plate was carried out at 8.5 and 9.4GHz using reflection intensity minimum point, and the difference of reflection intensity between Al_2O_3 and Cu-plate was observed reflecting their dielectric permittivity.