Hybrid STM/R-SNOM with novel probe

Abstract

A reflection-mode scanning near-field optical microscope joined with scanning tunneling microscope having a common revolving detection head and mounted on a classical optical microscope stage is proposed. This arrangement combines advantages of both near-field and far-field imageries and is able to display the images of surfaces with superresolution beyond the diffraction limit. Its function is characterized by the wide range of resolution and/or by the possibility to study different kinds of surfaces with nanometer-scale accuracy. A novel probe is used in the optical stage of the microscope. During its fabrication the light power of an Ar–Kr laser coupled to the single-mode fiber allows a local heating of a buffered HF solution in the vicinity of the extremity of fiber. By tuning the output power of the laser, the flux of energy at the very tip of the fiber varies, and different cone angles of the probe could be obtained. This process is faster than the classical chemical etching. The etching speed, and shapes of the fiber versus temperature are therefore discussed. A comparison of the two different images obtained with a STM and R-SNOM parts of the microscope is also presented.