title: Simultaneous current, force and dissipation measurements on the Si(111) 7×7 surface with an optimized qPlus AFM/STM technique.
abstract: We present the results of simultaneous scanning-tunneling and frequency-modulated dynamic atomic force microscopy measurements with a qPlus setup. The qPlus sensor is a purely electrical sensor based on a quartz tuning fork. If both the tunneling current and the force signal are to be measured at the tip, a cross-talk of the tunneling current with the force signal can easily occur. The origin and general features of the capacitive cross-talk will be discussed in detail in this contribution. Furthermore, we describe an experimental setup that improves the level of decoupling between the tunneling-current and the deflection signal. The efficiency of this experimental setup is demonstrated through topography and site-specific force/tunneling-spectroscopy measurements on the Si(111) 7×7 surface. The results show an excellent agreement with previously reported data measured by optical interferometric deflection.
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnicka 10, 162 53, Prague, Czech Republic.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Majzik
authors.forename: Martin
authors.initials: M
authors.lastname: Setvín
authors.forename: Andreas
authors.initials: A
authors.lastname: Bettac
authors.forename: Albrecht
authors.initials: A
authors.lastname: Feltz
authors.forename: Vladimír
authors.initials: V
authors.lastname: Cháb
authors.forename: Pavel
authors.initials: P
authors.lastname: Jelínek