Development of a self-sensing probe for local depositions in liquid condition

Abstract

This paper describes novel techniques of nanometre-scale measurement and surface modification using a scanning probe microscope (SPM) with a nanopipette probe. A glass nanopipette with an aperture approximately 200 nm in diameter was used as the SPM probe. Since the nanopipette can be filled with various kinds of materials inner side, it is possible to deposit the materials on a surface. However, in liquid condition, the deposition domain would become larger than the aperture of the nanopipette probe owing to the diffusion of the materials. To prevent the diffusion of the materials, an AFM with a method of frequency modulation was employed for the controlling of the distance between surface and the probe in liquid condition. In this study, self-sensing probe with the nanopipette was developed by using a tuning fork quartz crystal resonator to detect a probe oscillation. Frequency response characteristic of the probe was investigated. By utilising the probe-surface distance control based on the SPM technique, aperture-size deposition domain was achieved in liquid condition. This technique of local deposition in liquid condition would be applicable for various fields such as fabrication of micro- and nanometre-scale devices and arrangement of biological samples.