New fabrication technique for highly sensitive qPlus sensor with well-defined spring constant
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Sensitivity Enhancement of Soft Capacitive Pressure Sensors Using a Solvent Evaporation-Based Porosity Control Technique
Published on: March 24, 2023
Hatem Labidi1, Martin Kupsta2, Taleana Huff1
1Department of Physics, University of Alberta, Edmonton, AB, Canada, T6G 2J1; National Institute for Nanotechnology, National Research Council of Canada, Edmonton, AB, Canada, T6G 2M9.
Abstract:
A new technique for the fabrication of highly sensitive qPlus sensor for atomic force microscopy (AFM) is described. The focused ion beam was used to cut then weld onto a bare quartz tuning fork a sharp micro-tip from an electrochemically etched tungsten wire. The resulting qPlus sensor exhibits high resonance frequency and quality factor allowing increased force gradient sensitivity. Its spring constant can be determined precisely which allows accurate quantitative AFM measurements. The sensor is shown to be very stable and could undergo usual UHV tip cleaning including e-beam and field evaporation as well as in situ STM tip treatment. Preliminary results with STM and AFM atomic resolution imaging at 4.5 K of the silicon Si(111)-7×7 surface are presented.
