Articles you may be interested inA method to provide rapid in situ determination of tip radius in dynamic atomic force microscopy Rev. Sci. Instrum. 83, 043707 (2012); 10.1063/1.4704376 A method for calculating capacitances and electrostatic forces in atomic force microscopyWe present a method for in situ characterization of the tip shape in atomic force microscopes that can operate in noncontact ac mode. By sweeping the voltage between tip and sample while recording the sample position as it is regulated to give a constant force gradient, we obtain curves giving information about the tip geometry. The measurements were performed in ultrahigh vacuum using electrochemically etched tungsten tips against a surface of doped silicon. Our results show that the sphere model gives a good description of the interaction, and that the radii we obtain are consistent with data from scanning electron microscopy. The method can also be used to estimate the value of the Hamaker constant and the contact potential between tip and sample.
A compact scanning tunneling microscope (STM) with a novel rotary piezoelectric stepping motor for coarse positioning has been developed. An inertial method for rotating of the rotor by the pair of piezoplates has been used in the piezomotor. Minimal angular step size was about several arcsec with the spindle working torque up to 1 N×cm. Design of the STM was noticeably simplified by utilization of the piezomotor with such small step size. A shaft eccentrically attached to the piezomotor spindle made it possible to push and pull back the cylindrical bush with the tubular piezoscanner. A linear step of coarse positioning was about 50 nm. STM resolution in vertical direction was better than 0.1 nm without an external vibration isolation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.