In-depth measurement of 60GHz band near-field and transmission mode microscopy

The study on the near-field microscopy at the millimeter- and submillimeter-wave bands has been flourishing for diagnosis of bio-, nano- and micro-structures. In this research, the in-depth detection capability in the near-field by the transmission mode measurement at 60 GHz band has been investigated. First, the groove engraved with various depth of 0.1- 0.9 mm, the in-depth resolution is 0.5 mm. Second, the voids with 1 mm-dia are formed by various in-depths at 0.5-10 mm under the surface of Teflon. The void down to 2 mm can be detected. Final, a pore on the TiO₂ sheet with the thickness of 2.4 mm, it is shown in scanning the surface that a pore with about 0.8 mm-dia located at the surface can be detected.